Guide to the Secure Configuration of Red Hat Enterprise Linux 7

with profile Health Insurance Portability and Accountability Act (HIPAA)
The HIPAA Security Rule establishes U.S. national standards to protect individuals’ electronic personal health information that is created, received, used, or maintained by a covered entity. The Security Rule requires appropriate administrative, physical and technical safeguards to ensure the confidentiality, integrity, and security of electronic protected health information. This profile configures Red Hat Enterprise Linux 7 to the HIPAA Security Rule identified for securing of electronic protected health information. Use of this profile in no way guarantees or makes claims against legal compliance against the HIPAA Security Rule(s).
The SCAP Security Guide Project
https://www.open-scap.org/security-policies/scap-security-guide
This guide presents a catalog of security-relevant configuration settings for Red Hat Enterprise Linux 7. It is a rendering of content structured in the eXtensible Configuration Checklist Description Format (XCCDF) in order to support security automation. The SCAP content is is available in the scap-security-guide package which is developed at https://www.open-scap.org/security-policies/scap-security-guide.

Providing system administrators with such guidance informs them how to securely configure systems under their control in a variety of network roles. Policy makers and baseline creators can use this catalog of settings, with its associated references to higher-level security control catalogs, in order to assist them in security baseline creation. This guide is a catalog, not a checklist, and satisfaction of every item is not likely to be possible or sensible in many operational scenarios. However, the XCCDF format enables granular selection and adjustment of settings, and their association with OVAL and OCIL content provides an automated checking capability. Transformations of this document, and its associated automated checking content, are capable of providing baselines that meet a diverse set of policy objectives. Some example XCCDF Profiles, which are selections of items that form checklists and can be used as baselines, are available with this guide. They can be processed, in an automated fashion, with tools that support the Security Content Automation Protocol (SCAP). The DISA STIG, which provides required settings for US Department of Defense systems, is one example of a baseline created from this guidance.
Do not attempt to implement any of the settings in this guide without first testing them in a non-operational environment. The creators of this guidance assume no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic.

Profile Information

Profile TitleHealth Insurance Portability and Accountability Act (HIPAA)
Profile IDxccdf_org.ssgproject.content_profile_hipaa

CPE Platforms

  • cpe:/o:redhat:enterprise_linux:7::client
  • cpe:/o:redhat:enterprise_linux:7::computenode
  • cpe:/o:redhat:enterprise_linux:7::server
  • cpe:/o:redhat:enterprise_linux:7::workstation
  • cpe:/o:redhat:enterprise_linux:7

Revision History

Current version: 0.1.73

  • draft (as of 2024-05-08)

Table of Contents

  1. System Settings
    1. Installing and Maintaining Software
    2. Account and Access Control
    3. GRUB2 bootloader configuration
    4. Configure Syslog
    5. Network Configuration and Firewalls
    6. File Permissions and Masks
    7. SELinux
  2. Services
    1. Base Services
    2. Cron and At Daemons
    3. NFS and RPC
    4. Obsolete Services
    5. Network Routing
    6. SSH Server
  3. System Accounting with auditd
    1. Configure auditd Rules for Comprehensive Auditing
    2. Configure auditd Data Retention

Checklist

Group   Guide to the Secure Configuration of Red Hat Enterprise Linux 7   Group contains 54 groups and 142 rules
Group   System Settings   Group contains 27 groups and 38 rules
[ref]   Contains rules that check correct system settings.
Group   Installing and Maintaining Software   Group contains 7 groups and 10 rules
[ref]   The following sections contain information on security-relevant choices during the initial operating system installation process and the setup of software updates.
Group   System and Software Integrity   Group contains 2 groups and 2 rules
[ref]   System and software integrity can be gained by installing antivirus, increasing system encryption strength with FIPS, verifying installed software, enabling SELinux, installing an Intrusion Prevention System, etc. However, installing or enabling integrity checking tools cannot prevent intrusions, but they can detect that an intrusion may have occurred. Requirements for integrity checking may be highly dependent on the environment in which the system will be used. Snapshot-based approaches such as AIDE may induce considerable overhead in the presence of frequent software updates.
Group   Software Integrity Checking   Group contains 1 group and 2 rules
[ref]   Both the AIDE (Advanced Intrusion Detection Environment) software and the RPM package management system provide mechanisms for verifying the integrity of installed software. AIDE uses snapshots of file metadata (such as hashes) and compares these to current system files in order to detect changes.

The RPM package management system can conduct integrity checks by comparing information in its metadata database with files installed on the system.
Group   Verify Integrity with RPM   Group contains 2 rules
[ref]   The RPM package management system includes the ability to verify the integrity of installed packages by comparing the installed files with information about the files taken from the package metadata stored in the RPM database. Although an attacker could corrupt the RPM database (analogous to attacking the AIDE database as described above), this check can still reveal modification of important files. To list which files on the system differ from what is expected by the RPM database: 
$ rpm -qVa
See the man page for rpm to see a complete explanation of each column.

Rule   Verify File Hashes with RPM   [ref]

Without cryptographic integrity protections, system executables and files can be altered by unauthorized users without detection. The RPM package management system can check the hashes of installed software packages, including many that are important to system security. To verify that the cryptographic hash of system files and commands matches vendor values, run the following command to list which files on the system have hashes that differ from what is expected by the RPM database: 
$ rpm -Va --noconfig | grep '^..5'
If the file was not expected to change, investigate the cause of the change using audit logs or other means. The package can then be reinstalled to restore the file. Run the following command to determine which package owns the file: 
$ rpm -qf FILENAME
The package can be reinstalled from a yum repository using the command: 
$ sudo yum reinstall PACKAGENAME
Alternatively, the package can be reinstalled from trusted media using the command: 
$ sudo rpm -Uvh PACKAGENAME
Warning:  This rule can take a long time to perform the check and might consume a considerable amount of resources depending on the number of packages present on the system. It is not a problem in most cases, but especially systems with a large number of installed packages can be affected. See https://access.redhat.com/articles/6999111.
Rationale:
The hashes of important files like system executables should match the information given by the RPM database. Executables with erroneous hashes could be a sign of nefarious activity on the system.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_rpm_verify_hashes
Identifiers:

CCE-27157-7

References:
cis-csc11, 2, 3, 9
cjis5.10.4.1
cobit5APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02
cui3.3.8, 3.4.1
disaCCI-000366, CCI-001749
hipaa164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i)
isa-62443-20094.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4
isa-62443-2013SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4
nistCM-6(d), CM-6(c), SI-7, SI-7(1), SI-7(6), AU-9(3)
nist-csfPR.DS-6, PR.DS-8, PR.IP-1
pcidssReq-11.5
os-srgSRG-OS-000480-GPOS-00227
stigidRHEL-07-010020
pcidss411.5.2
stigrefSV-214799r854001_rule

Complexity:high
Disruption:medium
Reboot:false
Strategy:restrict
- name: 'Set fact: Package manager reinstall command'
  set_fact:
    package_manager_reinstall_cmd: yum reinstall -y
  when: ansible_distribution in [ "Fedora", "RedHat", "CentOS", "OracleLinux" ]
  tags:
  - CCE-27157-7
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010020
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_hashes

- name: 'Set fact: Package manager reinstall command (zypper)'
  set_fact:
    package_manager_reinstall_cmd: zypper in -f -y
  when: ansible_distribution == "SLES"
  tags:
  - CCE-27157-7
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010020
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_hashes

- name: Read files with incorrect hash
  command: rpm -Va --nodeps --nosize --nomtime --nordev --nocaps --nolinkto --nouser
    --nogroup --nomode --noghost --noconfig
  register: files_with_incorrect_hash
  changed_when: false
  failed_when: files_with_incorrect_hash.rc > 1
  check_mode: false
  when: (package_manager_reinstall_cmd is defined)
  tags:
  - CCE-27157-7
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010020
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_hashes

- name: Create list of packages
  command: rpm -qf "{{ item }}"
  with_items: '{{ files_with_incorrect_hash.stdout_lines | map(''regex_findall'',
    ''^[.]+[5]+.* (\/.*)'', ''\1'') | map(''join'') | select(''match'', ''(\/.*)'')
    | list | unique }}'
  register: list_of_packages
  changed_when: false
  check_mode: false
  when:
  - files_with_incorrect_hash.stdout_lines is defined
  - (files_with_incorrect_hash.stdout_lines | length > 0)
  tags:
  - CCE-27157-7
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010020
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_hashes

- name: Reinstall packages of files with incorrect hash
  command: '{{ package_manager_reinstall_cmd }} ''{{ item }}'''
  with_items: '{{ list_of_packages.results | map(attribute=''stdout_lines'') | list
    | unique }}'
  when:
  - files_with_incorrect_hash.stdout_lines is defined
  - (package_manager_reinstall_cmd is defined and (files_with_incorrect_hash.stdout_lines
    | length > 0))
  tags:
  - CCE-27157-7
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010020
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_hashes



# Find which files have incorrect hash (not in /etc, because of the system related config files) and then get files names
files_with_incorrect_hash="$(rpm -Va --noconfig | grep -E '^..5' | awk '{print $NF}' )"

if [ -n "$files_with_incorrect_hash" ]; then
    # From files names get package names and change newline to space, because rpm writes each package to new line
    packages_to_reinstall="$(rpm -qf $files_with_incorrect_hash | tr '\n' ' ')"

    
    yum reinstall -y $packages_to_reinstall
    
fi

Rule   Verify and Correct File Permissions with RPM   [ref]

The RPM package management system can check file access permissions of installed software packages, including many that are important to system security. Verify that the file permissions of system files and commands match vendor values. Check the file permissions with the following command: 
$ sudo rpm -Va | awk '{ if (substr($0,2,1)=="M") print $NF }'
Output indicates files that do not match vendor defaults. After locating a file with incorrect permissions, run the following command to determine which package owns it: 
$ rpm -qf FILENAME

Next, run the following command to reset its permissions to the correct values: 
$ sudo rpm --setperms PACKAGENAME
Warning:  Profiles may require that specific files have stricter file permissions than defined by the vendor. Such files will be reported as a finding and need to be evaluated according to your policy and deployment environment.
Warning:  This rule can take a long time to perform the check and might consume a considerable amount of resources depending on the number of packages present on the system. It is not a problem in most cases, but especially systems with a large number of installed packages can be affected. See https://access.redhat.com/articles/6999111.
Rationale:
Permissions on system binaries and configuration files that are too generous could allow an unauthorized user to gain privileges that they should not have. The permissions set by the vendor should be maintained. Any deviations from this baseline should be investigated.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_rpm_verify_permissions
Identifiers:

CCE-27209-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 5, 6, 9
cjis5.10.4.1
cobit5APO01.06, APO11.04, BAI03.05, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.04, DSS05.07, DSS06.02, MEA02.01
cui3.3.8, 3.4.1
disaCCI-001493, CCI-001494, CCI-001495, CCI-001496
hipaa164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i)
isa-62443-20094.3.3.3.9, 4.3.3.5.8, 4.3.3.7.3, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 5.2, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.5.1, A.12.6.2, A.12.7.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R4.2, CIP-003-8 R6, CIP-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2
nistCM-6(d), CM-6(c), SI-7, SI-7(1), SI-7(6), AU-9(3), CM-6(a)
nist-csfPR.AC-4, PR.DS-5, PR.IP-1, PR.PT-1
pcidssReq-11.5
os-srgSRG-OS-000256-GPOS-00097, SRG-OS-000257-GPOS-00098, SRG-OS-000258-GPOS-00099, SRG-OS-000278-GPOS-00108
stigidRHEL-07-010010
pcidss411.5.2
stigrefSV-204392r880752_rule

Complexity:high
Disruption:medium
Reboot:false
Strategy:restrict
- name: Read list of files with incorrect permissions
  command: rpm -Va --nodeps --nosignature --nofiledigest --nosize --nomtime --nordev
    --nocaps --nolinkto --nouser --nogroup
  register: files_with_incorrect_permissions
  failed_when: files_with_incorrect_permissions.rc > 1
  changed_when: false
  check_mode: false
  tags:
  - CCE-27209-6
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010010
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_permissions

- name: Create list of packages
  command: rpm -qf "{{ item }}"
  with_items: '{{ files_with_incorrect_permissions.stdout_lines | map(''regex_findall'',
    ''^[.]+[M]+.* (\/.*)'', ''\1'') | map(''join'') | select(''match'', ''(\/.*)'')
    | list | unique }}'
  register: list_of_packages
  changed_when: false
  check_mode: false
  when: (files_with_incorrect_permissions.stdout_lines | length > 0)
  tags:
  - CCE-27209-6
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010010
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_permissions

- name: Correct file permissions with RPM
  command: rpm --setperms '{{ item }}'
  with_items: '{{ list_of_packages.results | map(attribute=''stdout_lines'') | list
    | unique }}'
  when: (files_with_incorrect_permissions.stdout_lines | length > 0)
  tags:
  - CCE-27209-6
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010010
  - NIST-800-171-3.3.8
  - NIST-800-171-3.4.1
  - NIST-800-53-AU-9(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(c)
  - NIST-800-53-CM-6(d)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - NIST-800-53-SI-7(6)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - high_complexity
  - high_severity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy
  - rpm_verify_permissions

Complexity:high
Disruption:medium
Reboot:false
Strategy:restrict

# Declare array to hold set of RPM packages we need to correct permissions for
declare -A SETPERMS_RPM_DICT

# Create a list of files on the system having permissions different from what
# is expected by the RPM database
readarray -t FILES_WITH_INCORRECT_PERMS < <(rpm -Va --nofiledigest | awk '{ if (substr($0,2,1)=="M") print $NF }')

for FILE_PATH in "${FILES_WITH_INCORRECT_PERMS[@]}"
do
        # NOTE: some files maybe controlled by more then one package
        readarray -t RPM_PACKAGES < <(rpm -qf "${FILE_PATH}")
        for RPM_PACKAGE in "${RPM_PACKAGES[@]}"
        do
                # Use an associative array to store packages as it's keys, not having to care about duplicates.
                SETPERMS_RPM_DICT["$RPM_PACKAGE"]=1
        done
done

# For each of the RPM packages left in the list -- reset its permissions to the
# correct values
for RPM_PACKAGE in "${!SETPERMS_RPM_DICT[@]}"
do
	rpm --restore "${RPM_PACKAGE}"
done
Group   Disk Partitioning   Group contains 1 rule
[ref]   To ensure separation and protection of data, there are top-level system directories which should be placed on their own physical partition or logical volume. The installer's default partitioning scheme creates separate logical volumes for /, /boot, and swap.
  • If starting with any of the default layouts, check the box to \"Review and modify partitioning.\" This allows for the easy creation of additional logical volumes inside the volume group already created, though it may require making /'s logical volume smaller to create space. In general, using logical volumes is preferable to using partitions because they can be more easily adjusted later.
  • If creating a custom layout, create the partitions mentioned in the previous paragraph (which the installer will require anyway), as well as separate ones described in the following sections.
If a system has already been installed, and the default partitioning scheme was used, it is possible but nontrivial to modify it to create separate logical volumes for the directories listed above. The Logical Volume Manager (LVM) makes this possible. See the LVM HOWTO at http://tldp.org/HOWTO/LVM-HOWTO/ for more detailed information on LVM.

Rule   Encrypt Partitions   [ref]

Red Hat Enterprise Linux 7 natively supports partition encryption through the Linux Unified Key Setup-on-disk-format (LUKS) technology. The easiest way to encrypt a partition is during installation time.

For manual installations, select the Encrypt checkbox during partition creation to encrypt the partition. When this option is selected the system will prompt for a passphrase to use in decrypting the partition. The passphrase will subsequently need to be entered manually every time the system boots.

For automated/unattended installations, it is possible to use Kickstart by adding the --encrypted and --passphrase= options to the definition of each partition to be encrypted. For example, the following line would encrypt the root partition: 
part / --fstype=ext4 --size=100 --onpart=hda1 --encrypted --passphrase=PASSPHRASE
Any PASSPHRASE is stored in the Kickstart in plaintext, and the Kickstart must then be protected accordingly. Omitting the --passphrase= option from the partition definition will cause the installer to pause and interactively ask for the passphrase during installation.

By default, the Anaconda installer uses aes-xts-plain64 cipher with a minimum 512 bit key size which should be compatible with FIPS enabled.

Detailed information on encrypting partitions using LUKS or LUKS ciphers can be found on the Red Hat Enterprise Linux 7 Documentation web site:
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/security_guide/sec-encryption .
Rationale:
The risk of a system's physical compromise, particularly mobile systems such as laptops, places its data at risk of compromise. Encrypting this data mitigates the risk of its loss if the system is lost.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_encrypt_partitions
Identifiers:

CCE-27128-8

References:
cis-csc13, 14
cobit5APO01.06, BAI02.01, BAI06.01, DSS04.07, DSS05.03, DSS05.04, DSS05.07, DSS06.02, DSS06.06
cui3.13.16
disaCCI-001199, CCI-002475, CCI-002476
hipaa164.308(a)(1)(ii)(D), 164.308(b)(1), 164.310(d), 164.312(a)(1), 164.312(a)(2)(iii), 164.312(a)(2)(iv), 164.312(b), 164.312(c), 164.314(b)(2)(i), 164.312(d)
isa-62443-2013SR 3.4, SR 4.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R4.2, CIP-007-3 R5.1
nistCM-6(a), SC-28, SC-28(1), SC-13, AU-9(3)
nist-csfPR.DS-1, PR.DS-5
os-srgSRG-OS-000405-GPOS-00184, SRG-OS-000185-GPOS-00079, SRG-OS-000404-GPOS-00183
Group   GNOME Desktop Environment   Group contains 1 group and 3 rules
[ref]   GNOME is a graphical desktop environment bundled with many Linux distributions that allow users to easily interact with the operating system graphically rather than textually. The GNOME Graphical Display Manager (GDM) provides login, logout, and user switching contexts as well as display server management.

GNOME is developed by the GNOME Project and is considered the default Red Hat Graphical environment.

For more information on GNOME and the GNOME Project, see https://www.gnome.org.
Group   GNOME Remote Access Settings   Group contains 2 rules
[ref]   GNOME remote access settings that apply to the graphical interface.

Rule   Require Credential Prompting for Remote Access in GNOME3   [ref]

By default, GNOME does not require credentials when using Vino for remote access. To configure the system to require remote credentials, add or set authentication-methods to ['vnc'] in /etc/dconf/db/local.d/00-security-settings. For example: 
[org/gnome/Vino]
authentication-methods=['vnc']
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example: 
/org/gnome/Vino/authentication-methods
After the settings have been set, run dconf update.
Rationale:
Username and password prompting is required for remote access. Otherwise, non-authorized and nefarious users can access the system freely.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_remote_access_credential_prompt
Identifiers:

CCE-80120-9

References:
cui3.1.12
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)

Complexity:low
Disruption:medium
Reboot:false
Strategy:unknown
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80120-9
  - NIST-800-171-3.1.12
  - dconf_gnome_remote_access_credential_prompt
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Require Credential Prompting for Remote Access in GNOME3
  ini_file:
    dest: /etc/dconf/db/local.d/00-security-settings
    section: org/gnome/Vino
    option: authentication-methods
    value: '[''vnc'']'
    create: true
    no_extra_spaces: true
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80120-9
  - NIST-800-171-3.1.12
  - dconf_gnome_remote_access_credential_prompt
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Prevent user modification of GNOME3 Credential Prompting for Remote Access
  lineinfile:
    path: /etc/dconf/db/local.d/locks/00-security-settings-lock
    regexp: ^/org/gnome/Vino/authentication-methods$
    line: /org/gnome/Vino/authentication-methods
    create: true
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80120-9
  - NIST-800-171-3.1.12
  - dconf_gnome_remote_access_credential_prompt
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Dconf Update
  command: dconf update
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80120-9
  - NIST-800-171-3.1.12
  - dconf_gnome_remote_access_credential_prompt
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

# Check for setting in any of the DConf db directories
# If files contain ibus or distro, ignore them.
# The assignment assumes that individual filenames don't contain :
readarray -t SETTINGSFILES < <(grep -r "\\[org/gnome/Vino\\]" "/etc/dconf/db/" \
                                | grep -v 'distro\|ibus\|local.d' | cut -d":" -f1)
DCONFFILE="/etc/dconf/db/local.d/00-security-settings"
DBDIR="/etc/dconf/db/local.d"

mkdir -p "${DBDIR}"

# Comment out the configurations in databases different from the target one
if [ "${#SETTINGSFILES[@]}" -ne 0 ]
then
    if grep -q "^\\s*authentication-methods\\s*=" "${SETTINGSFILES[@]}"
    then
        
        sed -Ei "s/(^\s*)authentication-methods(\s*=)/#\1authentication-methods\2/g" "${SETTINGSFILES[@]}"
    fi
fi

[ ! -z "${DCONFFILE}" ] && echo "" >> "${DCONFFILE}"
if ! grep -q "\\[org/gnome/Vino\\]" "${DCONFFILE}"
then
    printf '%s\n' "[org/gnome/Vino]" >> ${DCONFFILE}
fi

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "['vnc']")"
if grep -q "^\\s*authentication-methods\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*authentication-methods\\s*=\\s*.*/authentication-methods=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/Vino\\]|a\\authentication-methods=${escaped_value}" "${DCONFFILE}"
fi

dconf update
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/Vino/authentication-methods$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|local.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/local.d/locks"

mkdir -p "${LOCKSFOLDER}"

# Comment out the configurations in databases different from the target one
if [[ ! -z "${LOCKFILES}" ]]
then
    sed -i -E "s|^/org/gnome/Vino/authentication-methods$|#&|" "${LOCKFILES[@]}"
fi

if ! grep -qr "^/org/gnome/Vino/authentication-methods$" /etc/dconf/db/local.d/
then
    echo "/org/gnome/Vino/authentication-methods" >> "/etc/dconf/db/local.d/locks/00-security-settings-lock"
fi

dconf update

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Require Encryption for Remote Access in GNOME3   [ref]

By default, GNOME requires encryption when using Vino for remote access. To prevent remote access encryption from being disabled, add or set require-encryption to true in /etc/dconf/db/local.d/00-security-settings. For example: 
[org/gnome/Vino]
require-encryption=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example: 
/org/gnome/Vino/require-encryption
After the settings have been set, run dconf update.
Rationale:
Open X displays allow an attacker to capture keystrokes and to execute commands remotely.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_remote_access_encryption
Identifiers:

CCE-80121-7

References:
cis-csc1, 11, 12, 13, 15, 16, 18, 20, 3, 4, 6, 9
cobit5BAI03.08, BAI07.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS03.01
cui3.1.13
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.4.3.2, 4.3.4.3.3, 4.4.3.3
isa-62443-2013SR 7.6
iso27001-2013A.12.1.1, A.12.1.2, A.12.1.4, A.12.5.1, A.12.6.2, A.13.1.1, A.13.1.2, A.14.2.2, A.14.2.3, A.14.2.4
nistCM-6(a), AC-17(a), AC-17(2)
nist-csfDE.AE-1, PR.DS-7, PR.IP-1
os-srgSRG-OS-000480-GPOS-00227

Complexity:low
Disruption:medium
Reboot:false
Strategy:unknown
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80121-7
  - NIST-800-171-3.1.13
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - dconf_gnome_remote_access_encryption
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Require Encryption for Remote Access in GNOME3
  ini_file:
    dest: /etc/dconf/db/local.d/00-security-settings
    section: org/gnome/Vino
    option: require-encryption
    value: 'true'
    create: true
    no_extra_spaces: true
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80121-7
  - NIST-800-171-3.1.13
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - dconf_gnome_remote_access_encryption
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Prevent user modification of GNOME3 Encryption for Remote Access
  lineinfile:
    path: /etc/dconf/db/local.d/locks/00-security-settings-lock
    regexp: ^/org/gnome/Vino/require-encryption$
    line: /org/gnome/Vino/require-encryption
    create: true
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80121-7
  - NIST-800-171-3.1.13
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - dconf_gnome_remote_access_encryption
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Dconf Update
  command: dconf update
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80121-7
  - NIST-800-171-3.1.13
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - dconf_gnome_remote_access_encryption
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

# Check for setting in any of the DConf db directories
# If files contain ibus or distro, ignore them.
# The assignment assumes that individual filenames don't contain :
readarray -t SETTINGSFILES < <(grep -r "\\[org/gnome/Vino\\]" "/etc/dconf/db/" \
                                | grep -v 'distro\|ibus\|local.d' | cut -d":" -f1)
DCONFFILE="/etc/dconf/db/local.d/00-security-settings"
DBDIR="/etc/dconf/db/local.d"

mkdir -p "${DBDIR}"

# Comment out the configurations in databases different from the target one
if [ "${#SETTINGSFILES[@]}" -ne 0 ]
then
    if grep -q "^\\s*require-encryption\\s*=" "${SETTINGSFILES[@]}"
    then
        
        sed -Ei "s/(^\s*)require-encryption(\s*=)/#\1require-encryption\2/g" "${SETTINGSFILES[@]}"
    fi
fi

[ ! -z "${DCONFFILE}" ] && echo "" >> "${DCONFFILE}"
if ! grep -q "\\[org/gnome/Vino\\]" "${DCONFFILE}"
then
    printf '%s\n' "[org/gnome/Vino]" >> ${DCONFFILE}
fi

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*require-encryption\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*require-encryption\\s*=\\s*.*/require-encryption=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/Vino\\]|a\\require-encryption=${escaped_value}" "${DCONFFILE}"
fi

dconf update
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/Vino/require-encryption$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|local.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/local.d/locks"

mkdir -p "${LOCKSFOLDER}"

# Comment out the configurations in databases different from the target one
if [[ ! -z "${LOCKFILES}" ]]
then
    sed -i -E "s|^/org/gnome/Vino/require-encryption$|#&|" "${LOCKFILES[@]}"
fi

if ! grep -qr "^/org/gnome/Vino/require-encryption$" /etc/dconf/db/local.d/
then
    echo "/org/gnome/Vino/require-encryption" >> "/etc/dconf/db/local.d/locks/00-security-settings-lock"
fi

dconf update

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Make sure that the dconf databases are up-to-date with regards to respective keyfiles   [ref]

By default, DConf uses a binary database as a data backend. The system-level database is compiled from keyfiles in the /etc/dconf/db/ directory by the 
dconf update
command. More specifically, content present in the following directories: 
/etc/dconf/db/gdm.d
/etc/dconf/db/local.d
Rationale:
Unlike text-based keyfiles, the binary database is impossible to check by OVAL. Therefore, in order to evaluate dconf configuration, both have to be true at the same time - configuration files have to be compliant, and the database needs to be more recent than those keyfiles, which gives confidence that it reflects them.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_dconf_db_up_to_date
Identifiers:

CCE-81004-4

References:
hipaa164.308(a)(1)(ii)(B), 164.308(a)(5)(ii)(A)
pcidssReq-6.2
os-srgSRG-OS-000480-GPOS-00227
cisreload_dconf_db
pcidss48.2.8

Complexity:low
Disruption:medium
Reboot:false
Strategy:unknown
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-81004-4
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-8.2.8
  - dconf_db_up_to_date
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
  - unknown_strategy

- name: Run dconf update
  ansible.builtin.command:
    cmd: dconf update
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-81004-4
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-8.2.8
  - dconf_db_up_to_date
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

dconf update

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Updating Software   Group contains 4 rules
[ref]   The yum command line tool is used to install and update software packages. The system also provides a graphical software update tool in the System menu, in the Administration submenu, called Software Update.

Red Hat Enterprise Linux 7 systems contain an installed software catalog called the RPM database, which records metadata of installed packages. Consistently using yum or the graphical Software Update for all software installation allows for insight into the current inventory of installed software on the system.

Rule   Ensure gpgcheck Enabled In Main yum Configuration   [ref]

The gpgcheck option controls whether RPM packages' signatures are always checked prior to installation. To configure yum to check package signatures before installing them, ensure the following line appears in /etc/yum.conf in the [main] section: 
gpgcheck=1
Rationale:
Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor.
Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA).
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_ensure_gpgcheck_globally_activated
Identifiers:

CCE-26989-4

References:
cis-csc11, 2, 3, 9
cjis5.10.4.1
cobit5APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02
cui3.4.8
disaCCI-001749
hipaa164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i)
isa-62443-20094.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4
isa-62443-2013SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4
nistCM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), SA-12, SA-12(10), CM-11(a), CM-11(b)
nist-csfPR.DS-6, PR.DS-8, PR.IP-1
osppFPT_TUD_EXT.1, FPT_TUD_EXT.2
pcidssReq-6.2
os-srgSRG-OS-000366-GPOS-00153
stigidRHEL-07-020050
anssiR59
cis1.2.2
pcidss46.3.3
stigrefSV-204447r877463_rule

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-26989-4
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-020050
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - configure_strategy
  - ensure_gpgcheck_globally_activated
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed

- name: Ensure GPG check is globally activated
  ini_file:
    dest: /etc/yum.conf
    section: main
    option: gpgcheck
    value: 1
    no_extra_spaces: true
    create: false
  when: '"yum" in ansible_facts.packages'
  tags:
  - CCE-26989-4
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-020050
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - configure_strategy
  - ensure_gpgcheck_globally_activated
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if rpm --quiet -q yum; then

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^gpgcheck")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^gpgcheck\\>" "/etc/yum.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^gpgcheck\\>.*/$escaped_formatted_output/gi" "/etc/yum.conf"
else
    if [[ -s "/etc/yum.conf" ]] && [[ -n "$(tail -c 1 -- "/etc/yum.conf" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/yum.conf"
    fi
    cce="CCE-26989-4"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/yum.conf" >> "/etc/yum.conf"
    printf '%s\n' "$formatted_output" >> "/etc/yum.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure gpgcheck Enabled for Local Packages   [ref]

yum should be configured to verify the signature(s) of local packages prior to installation. To configure yum to verify signatures of local packages, set the localpkg_gpgcheck to 1 in /etc/yum.conf.
Rationale:
Changes to any software components can have significant effects to the overall security of the operating system. This requirement ensures the software has not been tampered and has been provided by a trusted vendor.

Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_ensure_gpgcheck_local_packages
Identifiers:

CCE-80347-8

References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
cui3.4.8
disaCCI-001749
hipaa164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i)
isa-62443-20094.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 7.6
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4
nistCM-11(a), CM-11(b), CM-6(a), CM-5(3), SA-12, SA-12(10)
nist-csfPR.IP-1
osppFPT_TUD_EXT.1, FPT_TUD_EXT.2
os-srgSRG-OS-000366-GPOS-00153
stigidRHEL-07-020060
anssiR59
stigrefSV-204448r877463_rule

Complexity:low
Disruption:medium
Reboot:false
Strategy:unknown
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80347-8
  - DISA-STIG-RHEL-07-020060
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - ensure_gpgcheck_local_packages
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
  - unknown_strategy

- name: Ensure GPG check Enabled for Local Packages (yum)
  block:

  - name: Check stats of yum
    stat:
      path: /etc/yum.conf
    register: pkg

  - name: Check if config file of yum is a symlink
    ansible.builtin.set_fact:
      pkg_config_file_symlink: '{{ pkg.stat.lnk_target if pkg.stat.lnk_target is match("^/.*")
        else "/etc/yum.conf" | dirname ~ "/" ~ pkg.stat.lnk_target }}'
    when: pkg.stat.lnk_target is defined

  - name: Ensure GPG check Enabled for Local Packages (yum)
    ini_file:
      dest: '{{ pkg_config_file_symlink |  default("/etc/yum.conf") }}'
      section: main
      option: localpkg_gpgcheck
      value: 1
      no_extra_spaces: true
      create: true
  when: '"yum" in ansible_facts.packages'
  tags:
  - CCE-80347-8
  - DISA-STIG-RHEL-07-020060
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - ensure_gpgcheck_local_packages
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q yum; then

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^localpkg_gpgcheck")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^localpkg_gpgcheck\\>" "/etc/yum.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^localpkg_gpgcheck\\>.*/$escaped_formatted_output/gi" "/etc/yum.conf"
else
    if [[ -s "/etc/yum.conf" ]] && [[ -n "$(tail -c 1 -- "/etc/yum.conf" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/yum.conf"
    fi
    cce="CCE-80347-8"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/yum.conf" >> "/etc/yum.conf"
    printf '%s\n' "$formatted_output" >> "/etc/yum.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure gpgcheck Enabled for All yum Package Repositories   [ref]

To ensure signature checking is not disabled for any repos, remove any lines from files in /etc/yum.repos.d of the form: 
gpgcheck=0
Rationale:
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA)."
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_ensure_gpgcheck_never_disabled
Identifiers:

CCE-26876-3

References:
cis-csc11, 2, 3, 9
cjis5.10.4.1
cobit5APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02
cui3.4.8
disaCCI-001749
hipaa164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i)
isa-62443-20094.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4
isa-62443-2013SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4
nistCM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), SA-12, SA-12(10), CM-11(a), CM-11(b)
nist-csfPR.DS-6, PR.DS-8, PR.IP-1
osppFPT_TUD_EXT.1, FPT_TUD_EXT.2
pcidssReq-6.2
os-srgSRG-OS-000366-GPOS-00153
anssiR59
cis1.2.2
pcidss46.3.3

Complexity:low
Disruption:medium
Reboot:false
Strategy:enable
- name: Grep for yum repo section names
  shell: |
    set -o pipefail
    grep -HEr '^\[.+\]' -r /etc/yum.repos.d/
  register: repo_grep_results
  failed_when: repo_grep_results.rc not in [0, 1]
  changed_when: false
  tags:
  - CCE-26876-3
  - CJIS-5.10.4.1
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - enable_strategy
  - ensure_gpgcheck_never_disabled
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed

- name: Set gpgcheck=1 for each yum repo
  ini_file:
    path: '{{ item[0] }}'
    section: '{{ item[1] }}'
    option: gpgcheck
    value: '1'
    no_extra_spaces: true
  loop: '{{ repo_grep_results.stdout |regex_findall( ''(.+\.repo):\[(.+)\]\n?'' )
    if repo_grep_results is not skipped else [] }}'
  when: repo_grep_results is not skipped
  tags:
  - CCE-26876-3
  - CJIS-5.10.4.1
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - enable_strategy
  - ensure_gpgcheck_never_disabled
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed



sed -i 's/gpgcheck\s*=.*/gpgcheck=1/g' /etc/yum.repos.d/*

Rule   Ensure Red Hat GPG Key Installed   [ref]

To ensure the system can cryptographically verify base software packages come from Red Hat (and to connect to the Red Hat Network to receive them), the Red Hat GPG key must properly be installed. To install the Red Hat GPG key, run: 
$ sudo subscription-manager register
If the system is not connected to the Internet or an RHN Satellite, then install the Red Hat GPG key from trusted media such as the Red Hat installation CD-ROM or DVD. Assuming the disc is mounted in /media/cdrom, use the following command as the root user to import it into the keyring: 
$ sudo rpm --import /media/cdrom/RPM-GPG-KEY
Alternatively, the key may be pre-loaded during the RHEL installation. In such cases, the key can be installed by running the following command: 
sudo rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release
Rationale:
Changes to software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor. The Red Hat GPG key is necessary to cryptographically verify packages are from Red Hat.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_ensure_redhat_gpgkey_installed
Identifiers:

CCE-26957-1

References:
cis-csc11, 2, 3, 9
cjis5.10.4.1
cobit5APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02
cui3.4.8
disaCCI-001749
hipaa164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i)
isa-62443-20094.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4
isa-62443-2013SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4
nerc-cipCIP-003-8 R4.2, CIP-003-8 R6, CIP-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-5(3), SI-7, SC-12, SC-12(3), CM-6(a)
nist-csfPR.DS-6, PR.DS-8, PR.IP-1
osppFPT_TUD_EXT.1, FPT_TUD_EXT.2
pcidssReq-6.2
os-srgSRG-OS-000366-GPOS-00153
stigidRHEL-07-010019
anssiR59
pcidss46.3.3
stigrefSV-256968r902687_rule

Complexity:medium
Disruption:medium
Reboot:false
Strategy:restrict
- name: Read permission of GPG key directory
  stat:
    path: /etc/pki/rpm-gpg/
  register: gpg_key_directory_permission
  check_mode: false
  tags:
  - CCE-26957-1
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010019
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - ensure_redhat_gpgkey_installed
  - high_severity
  - medium_complexity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy

- name: Read signatures in GPG key
  command: gpg --with-fingerprint --with-colons "/etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release"
  changed_when: false
  register: gpg_fingerprints
  check_mode: false
  tags:
  - CCE-26957-1
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010019
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - ensure_redhat_gpgkey_installed
  - high_severity
  - medium_complexity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy

- name: Set Fact - Installed GPG Fingerprints
  set_fact:
    gpg_installed_fingerprints: |-
      {{ gpg_fingerprints.stdout | regex_findall('^pub.*
      (?:^fpr[:]*)([0-9A-Fa-f]*)', '\1') | list }}
  tags:
  - CCE-26957-1
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010019
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - ensure_redhat_gpgkey_installed
  - high_severity
  - medium_complexity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy

- name: Set Fact - Valid fingerprints
  set_fact:
    gpg_valid_fingerprints:
    - 567E347AD0044ADE55BA8A5F199E2F91FD431D51
    - 43A6E49C4A38F4BE9ABF2A5345689C882FA658E0
  tags:
  - CCE-26957-1
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010019
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - ensure_redhat_gpgkey_installed
  - high_severity
  - medium_complexity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy

- name: Import RedHat GPG key
  rpm_key:
    state: present
    key: /etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release
  when:
  - gpg_key_directory_permission.stat.mode <= '0755'
  - (gpg_installed_fingerprints | difference(gpg_valid_fingerprints)) | length ==
    0
  - gpg_installed_fingerprints | length > 0
  - ansible_distribution == "RedHat"
  tags:
  - CCE-26957-1
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-010019
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - PCI-DSSv4-6.3.3
  - ensure_redhat_gpgkey_installed
  - high_severity
  - medium_complexity
  - medium_disruption
  - no_reboot_needed
  - restrict_strategy


# The two fingerprints below are retrieved from https://access.redhat.com/security/team/key
readonly REDHAT_RELEASE_FINGERPRINT="567E347AD0044ADE55BA8A5F199E2F91FD431D51"
readonly REDHAT_AUXILIARY_FINGERPRINT="43A6E49C4A38F4BE9ABF2A5345689C882FA658E0"

# Location of the key we would like to import (once it's integrity verified)
readonly REDHAT_RELEASE_KEY="/etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release"

RPM_GPG_DIR_PERMS=$(stat -c %a "$(dirname "$REDHAT_RELEASE_KEY")")

# Verify /etc/pki/rpm-gpg directory permissions are safe
if [ "${RPM_GPG_DIR_PERMS}" -le "755" ]
then
  # If they are safe, try to obtain fingerprints from the key file
  # (to ensure there won't be e.g. CRC error).

  readarray -t GPG_OUT < <(gpg --with-fingerprint --with-colons "$REDHAT_RELEASE_KEY" | grep "^fpr" | cut -d ":" -f 10)

  GPG_RESULT=$?
  # No CRC error, safe to proceed
  if [ "${GPG_RESULT}" -eq "0" ]
  then
    echo "${GPG_OUT[*]}" | grep -vE "${REDHAT_RELEASE_FINGERPRINT}|${REDHAT_AUXILIARY_FINGERPRINT}" || {
      # If $REDHAT_RELEASE_KEY file doesn't contain any keys with unknown fingerprint, import it
      rpm --import "${REDHAT_RELEASE_KEY}"
    }
  fi
fi
Group   Account and Access Control   Group contains 4 groups and 9 rules
[ref]   In traditional Unix security, if an attacker gains shell access to a certain login account, they can perform any action or access any file to which that account has access. Therefore, making it more difficult for unauthorized people to gain shell access to accounts, particularly to privileged accounts, is a necessary part of securing a system. This section introduces mechanisms for restricting access to accounts under Red Hat Enterprise Linux 7.
Group   Protect Physical Console Access   Group contains 5 rules
[ref]   It is impossible to fully protect a system from an attacker with physical access, so securing the space in which the system is located should be considered a necessary step. However, there are some steps which, if taken, make it more difficult for an attacker to quickly or undetectably modify a system from its console.

Rule   Disable debug-shell SystemD Service   [ref]

SystemD's debug-shell service is intended to diagnose SystemD related boot issues with various systemctl commands. Once enabled and following a system reboot, the root shell will be available on tty9 which is access by pressing CTRL-ALT-F9. The debug-shell service should only be used for SystemD related issues and should otherwise be disabled.

By default, the debug-shell SystemD service is already disabled. The debug-shell service can be disabled with the following command: 
$ sudo systemctl mask --now debug-shell.service
Rationale:
This prevents attackers with physical access from trivially bypassing security on the machine through valid troubleshooting configurations and gaining root access when the system is rebooted.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_debug-shell_disabled
Identifiers:

CCE-80206-6

References:
cui3.4.5
disaCCI-000366
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
nistCM-6
osppFIA_UAU.1
os-srgSRG-OS-000324-GPOS-00125, SRG-OS-000480-GPOS-00227


[customizations.services]
masked = ["debug-shell"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable debug-shell SystemD Service - Collect systemd Services Present in
    the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80206-6
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_debug-shell_disabled

- name: Disable debug-shell SystemD Service - Ensure debug-shell.service is Masked
  ansible.builtin.systemd:
    name: debug-shell.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("debug-shell.service", multiline=True)
  tags:
  - CCE-80206-6
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_debug-shell_disabled

- name: Unit Socket Exists - debug-shell.socket
  ansible.builtin.command: systemctl -q list-unit-files debug-shell.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80206-6
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_debug-shell_disabled

- name: Disable debug-shell SystemD Service - Disable Socket debug-shell
  ansible.builtin.systemd:
    name: debug-shell.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("debug-shell.socket", multiline=True)
  tags:
  - CCE-80206-6
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_debug-shell_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_debug-shell

class disable_debug-shell {
  service {'debug-shell':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'debug-shell.service'
"$SYSTEMCTL_EXEC" disable 'debug-shell.service'
"$SYSTEMCTL_EXEC" mask 'debug-shell.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files debug-shell.socket; then
    "$SYSTEMCTL_EXEC" stop 'debug-shell.socket'
    "$SYSTEMCTL_EXEC" mask 'debug-shell.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'debug-shell.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: debug-shell.service
        enabled: false
        mask: true
      - name: debug-shell.socket
        enabled: false
        mask: true

Rule   Disable Ctrl-Alt-Del Burst Action   [ref]

By default, SystemD will reboot the system if the Ctrl-Alt-Del key sequence is pressed Ctrl-Alt-Delete more than 7 times in 2 seconds.

To configure the system to ignore the CtrlAltDelBurstAction setting, add or modify the following to /etc/systemd/system.conf: 
CtrlAltDelBurstAction=none
Warning:  Disabling the Ctrl-Alt-Del key sequence in /etc/init/control-alt-delete.conf DOES NOT disable the Ctrl-Alt-Del key sequence if running in runlevel 6 (e.g. in GNOME, KDE, etc.)! The Ctrl-Alt-Del key sequence will only be disabled if running in the non-graphical runlevel 3.
Rationale:
A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_disable_ctrlaltdel_burstaction
Identifiers:

CCE-80449-2

References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.4.5
disaCCI-000366
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2
nistCM-6(a), AC-6(1), CM-6(a)
nist-csfPR.AC-4, PR.DS-5
osppFAU_GEN.1.2
os-srgSRG-OS-000324-GPOS-00125, SRG-OS-000480-GPOS-00227

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80449-2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - disable_ctrlaltdel_burstaction
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed

- name: Disable Ctrl-Alt-Del Burst Action
  lineinfile:
    dest: /etc/systemd/system.conf
    state: present
    regexp: ^CtrlAltDelBurstAction
    line: CtrlAltDelBurstAction=none
    create: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"systemd" in ansible_facts.packages'
  tags:
  - CCE-80449-2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - disable_ctrlaltdel_burstaction
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q systemd; }; then

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^CtrlAltDelBurstAction=")

# shellcheck disable=SC2059
printf -v formatted_output "%s=%s" "$stripped_key" "none"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^CtrlAltDelBurstAction=\\>" "/etc/systemd/system.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^CtrlAltDelBurstAction=\\>.*/$escaped_formatted_output/gi" "/etc/systemd/system.conf"
else
    if [[ -s "/etc/systemd/system.conf" ]] && [[ -n "$(tail -c 1 -- "/etc/systemd/system.conf" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/systemd/system.conf"
    fi
    cce="CCE-80449-2"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/systemd/system.conf" >> "/etc/systemd/system.conf"
    printf '%s\n' "$formatted_output" >> "/etc/systemd/system.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,CtrlAltDelBurstAction%3Dnone
        mode: 0644
        path: /etc/systemd/system.conf.d/disable_ctrlaltdelete_burstaction.conf
        overwrite: true

Rule   Disable Ctrl-Alt-Del Reboot Activation   [ref]

By default, SystemD will reboot the system if the Ctrl-Alt-Del key sequence is pressed.

To configure the system to ignore the Ctrl-Alt-Del key sequence from the command line instead of rebooting the system, do either of the following: 
ln -sf /dev/null /etc/systemd/system/ctrl-alt-del.target
or 
systemctl mask ctrl-alt-del.target


Do not simply delete the /usr/lib/systemd/system/ctrl-alt-del.service file, as this file may be restored during future system updates.
Rationale:
A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_disable_ctrlaltdel_reboot
Identifiers:

CCE-27511-5

References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.4.5
disaCCI-000366
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2
nistCM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
osppFAU_GEN.1.2
os-srgSRG-OS-000324-GPOS-00125, SRG-OS-000480-GPOS-00227
stigidRHEL-07-020230
stigrefSV-204455r928574_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable Ctrl-Alt-Del Reboot Activation
  systemd:
    name: ctrl-alt-del.target
    force: true
    masked: true
    state: stopped
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27511-5
  - DISA-STIG-RHEL-07-020230
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - disable_ctrlaltdel_reboot
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

systemctl disable --now ctrl-alt-del.target
systemctl mask --now ctrl-alt-del.target

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: ctrl-alt-del.target
        mask: true

Rule   Verify that Interactive Boot is Disabled   [ref]

Red Hat Enterprise Linux 7 systems support an "interactive boot" option that can be used to prevent services from being started. On a Red Hat Enterprise Linux 7 system, interactive boot can be enabled by providing a 1, yes, true, or on value to the systemd.confirm_spawn kernel argument in /etc/default/grub. Remove any instance of 
systemd.confirm_spawn=(1|yes|true|on)
from the kernel arguments in that file to disable interactive boot. Recovery booting must also be disabled. Confirm that GRUB_DISABLE_RECOVERY=true is set in /etc/default/grub. It is also required to change the runtime configuration, run: 
/sbin/grubby --update-kernel=ALL --remove-args="systemd.confirm_spawn"
grub2-mkconfig -o /boot/grub2/grub.cfg
Rationale:
Using interactive or recovery boot, the console user could disable auditing, firewalls, or other services, weakening system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_grub2_disable_interactive_boot
Identifiers:

CCE-27335-9

References:
cis-csc11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06
cui3.1.2, 3.4.5
disaCCI-000213
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
iso27001-2013A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistSC-2(1), CM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.PT-3
osppFIA_UAU.1
os-srgSRG-OS-000480-GPOS-00227

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27335-9
  - NIST-800-171-3.1.2
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-2(1)
  - grub2_disable_interactive_boot
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Verify GRUB_DISABLE_RECOVERY=true
  lineinfile:
    path: /etc/default/grub
    regexp: ^GRUB_DISABLE_RECOVERY=.*
    line: GRUB_DISABLE_RECOVERY=true
    state: present
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27335-9
  - NIST-800-171-3.1.2
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-2(1)
  - grub2_disable_interactive_boot
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Verify that Interactive Boot is Disabled in /etc/default/grub
  replace:
    dest: /etc/default/grub
    regexp: systemd.confirm_spawn(=(1|yes|true|on)|\b)
    replace: systemd.confirm_spawn=no
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27335-9
  - NIST-800-171-3.1.2
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-2(1)
  - grub2_disable_interactive_boot
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Verify that Interactive Boot is Disabled (runtime)
  command: /sbin/grubby --update-kernel=ALL --remove-args="systemd.confirm_spawn"
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27335-9
  - NIST-800-171-3.1.2
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-2(1)
  - grub2_disable_interactive_boot
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Regen grub.cfg handle updated GRUB_DISABLE_RECOVERY and confirm_spawn
  command: grub2-mkconfig -o  /boot/grub2/grub.cfg
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27335-9
  - NIST-800-171-3.1.2
  - NIST-800-171-3.4.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-2(1)
  - grub2_disable_interactive_boot
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

# Verify that Interactive Boot is Disabled in /etc/default/grub
CONFIRM_SPAWN_YES="systemd.confirm_spawn\(=\(1\|yes\|true\|on\)\|\b\)"
CONFIRM_SPAWN_NO="systemd.confirm_spawn=no"

if grep -q "\(GRUB_CMDLINE_LINUX\|GRUB_CMDLINE_LINUX_DEFAULT\)" /etc/default/grub
then
	sed -i "s/${CONFIRM_SPAWN_YES}/${CONFIRM_SPAWN_NO}/" /etc/default/grub
fi

# make sure GRUB_DISABLE_RECOVERY=true
if grep -q '^GRUB_DISABLE_RECOVERY=.*'  '/etc/default/grub' ; then
       # modify the GRUB command-line if an GRUB_DISABLE_RECOVERY= arg already exists
       sed -i 's/GRUB_DISABLE_RECOVERY=.*/GRUB_DISABLE_RECOVERY=true/' /etc/default/grub
else
       # no GRUB_DISABLE_RECOVERY=arg is present, append it to file
       echo "GRUB_DISABLE_RECOVERY=true"  >> '/etc/default/grub'
fi



# Remove 'systemd.confirm_spawn' kernel argument also from runtime settings
/sbin/grubby --update-kernel=ALL --remove-args="systemd.confirm_spawn"


#Regen grub.cfg handle updated GRUB_DISABLE_RECOVERY and confirm_spawn
grub2-mkconfig -o /boot/grub2/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Require Authentication for Single User Mode   [ref]

Single-user mode is intended as a system recovery method, providing a single user root access to the system by providing a boot option at startup.

By default, single-user mode is protected by requiring a password and is set in /usr/lib/systemd/system/rescue.service.
Rationale:
This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_require_singleuser_auth
Identifiers:

CCE-27287-2

References:
cis-csc1, 11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
cui3.1.1, 3.4.5
disaCCI-000213
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
iso27001-2013A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3
nistIA-2, AC-3, CM-6(a)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3
osppFIA_UAU.1
os-srgSRG-OS-000080-GPOS-00048
stigidRHEL-07-010481
cis1.3.3
stigrefSV-204437r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Require single user mode password
  lineinfile:
    create: true
    dest: /usr/lib/systemd/system/rescue.service
    regexp: ^#?ExecStart=
    line: ExecStart=-/bin/sh -c "/usr/sbin/sulogin; /usr/bin/systemctl --fail --no-block
      default"
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27287-2
  - DISA-STIG-RHEL-07-010481
  - NIST-800-171-3.1.1
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-2
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - require_singleuser_auth
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

service_file="/usr/lib/systemd/system/rescue.service"

sulogin='/bin/sh -c "/usr/sbin/sulogin; /usr/bin/systemctl --fail --no-block default"'

if grep "^ExecStart=.*" "$service_file" ; then
    sed -i "s%^ExecStart=.*%ExecStart=-$sulogin%" "$service_file"
else
    echo "ExecStart=-$sulogin" >> "$service_file"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Protect Accounts by Restricting Password-Based Login   Group contains 2 groups and 4 rules
[ref]   Conventionally, Unix shell accounts are accessed by providing a username and password to a login program, which tests these values for correctness using the /etc/passwd and /etc/shadow files. Password-based login is vulnerable to guessing of weak passwords, and to sniffing and man-in-the-middle attacks against passwords entered over a network or at an insecure console. Therefore, mechanisms for accessing accounts by entering usernames and passwords should be restricted to those which are operationally necessary.
Group   Verify Proper Storage and Existence of Password Hashes   Group contains 1 rule
[ref]   By default, password hashes for local accounts are stored in the second field (colon-separated) in /etc/shadow. This file should be readable only by processes running with root credentials, preventing users from casually accessing others' password hashes and attempting to crack them. However, it remains possible to misconfigure the system and store password hashes in world-readable files such as /etc/passwd, or to even store passwords themselves in plaintext on the system. Using system-provided tools for password change/creation should allow administrators to avoid such misconfiguration.

Rule   Prevent Login to Accounts With Empty Password   [ref]

If an account is configured for password authentication but does not have an assigned password, it may be possible to log into the account without authentication. Remove any instances of the nullok in /etc/pam.d/system-auth and /etc/pam.d/password-auth to prevent logins with empty passwords.
Warning:  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. Note that this rule is not applicable for systems running within a container. Having user with empty password within a container is not considered a risk, because it should not be possible to directly login into a container anyway.
Rationale:
If an account has an empty password, anyone could log in and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_no_empty_passwords
Identifiers:

CCE-27286-4

References:
cis-csc1, 12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2
cobit5APO01.06, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.02, DSS06.03, DSS06.10
cui3.1.1, 3.1.5
disaCCI-000366
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.18.1.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistIA-5(1)(a), IA-5(c), CM-6(a)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.DS-5
osppFIA_UAU.1
pcidssReq-8.2.3
os-srgSRG-OS-000480-GPOS-00227
stigidRHEL-07-010290
cis4.4.2.4.1
pcidss48.3.1
stigrefSV-204424r880839_rule

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Prevent Login to Accounts With Empty Password - Check if system relies on
    authselect
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27286-4
  - CJIS-5.5.2
  - DISA-STIG-RHEL-07-010290
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3.1
  - configure_strategy
  - high_severity
  - low_complexity
  - medium_disruption
  - no_empty_passwords
  - no_reboot_needed

- name: Prevent Login to Accounts With Empty Password - Remediate using authselect
  block:

  - name: Prevent Login to Accounts With Empty Password - Check integrity of authselect
      current profile
    ansible.builtin.command:
      cmd: authselect check
    register: result_authselect_check_cmd
    changed_when: false
    failed_when: false

  - name: Prevent Login to Accounts With Empty Password - Informative message based
      on the authselect integrity check result
    ansible.builtin.assert:
      that:
      - result_authselect_check_cmd.rc == 0
      fail_msg:
      - authselect integrity check failed. Remediation aborted!
      - This remediation could not be applied because an authselect profile was not
        selected or the selected profile is not intact.
      - It is not recommended to manually edit the PAM files when authselect tool
        is available.
      - In cases where the default authselect profile does not cover a specific demand,
        a custom authselect profile is recommended.
      success_msg:
      - authselect integrity check passed

  - name: Prevent Login to Accounts With Empty Password - Get authselect current features
    ansible.builtin.shell:
      cmd: authselect current | tail -n+3 | awk '{ print $2 }'
    register: result_authselect_features
    changed_when: false
    when:
    - result_authselect_check_cmd is success

  - name: Prevent Login to Accounts With Empty Password - Ensure "without-nullok"
      feature is enabled using authselect tool
    ansible.builtin.command:
      cmd: authselect enable-feature without-nullok
    register: result_authselect_enable_feature_cmd
    when:
    - result_authselect_check_cmd is success
    - result_authselect_features.stdout is not search("without-nullok")

  - name: Prevent Login to Accounts With Empty Password - Ensure authselect changes
      are applied
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_enable_feature_cmd is not skipped
    - result_authselect_enable_feature_cmd is success
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - result_authselect_present.stat.exists
  tags:
  - CCE-27286-4
  - CJIS-5.5.2
  - DISA-STIG-RHEL-07-010290
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3.1
  - configure_strategy
  - high_severity
  - low_complexity
  - medium_disruption
  - no_empty_passwords
  - no_reboot_needed

- name: Prevent Login to Accounts With Empty Password - Remediate directly editing
    PAM files
  ansible.builtin.replace:
    dest: '{{ item }}'
    regexp: nullok
  loop:
  - /etc/pam.d/system-auth
  - /etc/pam.d/password-auth
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not result_authselect_present.stat.exists
  tags:
  - CCE-27286-4
  - CJIS-5.5.2
  - DISA-STIG-RHEL-07-010290
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3.1
  - configure_strategy
  - high_severity
  - low_complexity
  - medium_disruption
  - no_empty_passwords
  - no_reboot_needed

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -f /usr/bin/authselect ]; then
    if ! authselect check; then
echo "
authselect integrity check failed. Remediation aborted!
This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
It is not recommended to manually edit the PAM files when authselect tool is available.
In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
exit 1
fi
authselect enable-feature without-nullok

authselect apply-changes -b
else
    
if grep -qP '^\s*auth\s+'"sufficient"'\s+pam_unix.so\s.*\bnullok\b' "/etc/pam.d/system-auth"; then
    sed -i -E --follow-symlinks 's/(.*auth.*'"sufficient"'.*pam_unix.so.*)\snullok=?[[:alnum:]]*(.*)/\1\2/g' "/etc/pam.d/system-auth"
fi
    
if grep -qP '^\s*password\s+'"sufficient"'\s+pam_unix.so\s.*\bnullok\b' "/etc/pam.d/system-auth"; then
    sed -i -E --follow-symlinks 's/(.*password.*'"sufficient"'.*pam_unix.so.*)\snullok=?[[:alnum:]]*(.*)/\1\2/g' "/etc/pam.d/system-auth"
fi
    
if grep -qP '^\s*auth\s+'"sufficient"'\s+pam_unix.so\s.*\bnullok\b' "/etc/pam.d/password-auth"; then
    sed -i -E --follow-symlinks 's/(.*auth.*'"sufficient"'.*pam_unix.so.*)\snullok=?[[:alnum:]]*(.*)/\1\2/g' "/etc/pam.d/password-auth"
fi
    
if grep -qP '^\s*password\s+'"sufficient"'\s+pam_unix.so\s.*\bnullok\b' "/etc/pam.d/password-auth"; then
    sed -i -E --follow-symlinks 's/(.*password.*'"sufficient"'.*pam_unix.so.*)\snullok=?[[:alnum:]]*(.*)/\1\2/g' "/etc/pam.d/password-auth"
fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,%23%20Generated%20by%20authselect%20on%20Sat%20Oct%2027%2014%3A59%3A36%202018%0A%23%20Do%20not%20modify%20this%20file%20manually.%0A%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_env.so%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_faildelay.so%20delay%3D2000000%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_fprintd.so%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20try_first_pass%0Aauth%20%20%20%20%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet_success%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20forward_pass%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3C%201000%20quiet%0Aaccount%20%20%20%20%20%5Bdefault%3Dbad%20success%3Dok%20user_unknown%3Dignore%5D%20pam_sss.so%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_permit.so%0A%0Apassword%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_pwquality.so%20try_first_pass%20local_users_only%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20sha512%20shadow%20try_first_pass%20use_authtok%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20use_authtok%0Apassword%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_keyinit.so%20revoke%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_limits.so%0A-session%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_systemd.so%0Asession%20%20%20%20%20%5Bsuccess%3D1%20default%3Dignore%5D%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20service%20in%20crond%20quiet%20use_uid%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%0A
        mode: 0644
        path: /etc/pam.d/password-auth
        overwrite: true
      - contents:
          source: data:,%23%20Generated%20by%20authselect%20on%20Sat%20Oct%2027%2014%3A59%3A36%202018%0A%23%20Do%20not%20modify%20this%20file%20manually.%0A%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_env.so%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_faildelay.so%20delay%3D2000000%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_fprintd.so%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet%0Aauth%20%20%20%20%20%20%20%20%5Bdefault%3D1%20ignore%3Dignore%20success%3Dok%5D%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20try_first_pass%0Aauth%20%20%20%20%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3E%3D%201000%20quiet_success%0Aauth%20%20%20%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20forward_pass%0Aauth%20%20%20%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_localuser.so%0Aaccount%20%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20uid%20%3C%201000%20quiet%0Aaccount%20%20%20%20%20%5Bdefault%3Dbad%20success%3Dok%20user_unknown%3Dignore%5D%20pam_sss.so%0Aaccount%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_permit.so%0A%0Apassword%20%20%20%20requisite%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_pwquality.so%20try_first_pass%20local_users_only%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%20sha512%20shadow%20try_first_pass%20use_authtok%0Apassword%20%20%20%20sufficient%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%20use_authtok%0Apassword%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_deny.so%0A%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_keyinit.so%20revoke%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_limits.so%0A-session%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_systemd.so%0Asession%20%20%20%20%20%5Bsuccess%3D1%20default%3Dignore%5D%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_succeed_if.so%20service%20in%20crond%20quiet%20use_uid%0Asession%20%20%20%20%20required%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_unix.so%0Asession%20%20%20%20%20optional%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20pam_sss.so%0A
        mode: 0644
        path: /etc/pam.d/system-auth
        overwrite: true
Group   Restrict Root Logins   Group contains 3 rules
[ref]   Direct root logins should be allowed only for emergency use. In normal situations, the administrator should access the system via a unique unprivileged account, and then use su or sudo to execute privileged commands. Discouraging administrators from accessing the root account directly ensures an audit trail in organizations with multiple administrators. Locking down the channels through which root can connect directly also reduces opportunities for password-guessing against the root account. The login program uses the file /etc/securetty to determine which interfaces should allow root logins. The virtual devices /dev/console and /dev/tty* represent the system consoles (accessible via the Ctrl-Alt-F1 through Ctrl-Alt-F6 keyboard sequences on a default installation). The default securetty file also contains /dev/vc/*. These are likely to be deprecated in most environments, but may be retained for compatibility. Root should also be prohibited from connecting via network protocols. Other sections of this document include guidance describing how to prevent root from logging in via SSH.

Rule   Direct root Logins Not Allowed   [ref]

To further limit access to the root account, administrators can disable root logins at the console by editing the /etc/securetty file. This file lists all devices the root user is allowed to login to. If the file does not exist at all, the root user can login through any communication device on the system, whether via the console or via a raw network interface. This is dangerous as user can login to the system as root via Telnet, which sends the password in plain text over the network. By default, Red Hat Enterprise Linux 7's /etc/securetty file only allows the root user to login at the console physically attached to the system. To prevent root from logging in, remove the contents of this file. To prevent direct root logins, remove the contents of this file by typing the following command: 
$ sudo echo > /etc/securetty
Warning:  This rule only checks the /etc/securetty file existence and its content. If you need to restrict user access using the /etc/securetty file, make sure the pam_securetty.so PAM module is properly enabled in relevant PAM files.
Rationale:
Disabling direct root logins ensures proper accountability and multifactor authentication to privileged accounts. Users will first login, then escalate to privileged (root) access via su / sudo. This is required for FISMA Low and FISMA Moderate systems.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_direct_root_logins
Identifiers:

CCE-27294-8

References:
cis-csc1, 12, 15, 16, 5
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.1.1, 3.1.6
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1
iso27001-2013A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3
nistIA-2, CM-6(a)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
anssiR33
pcidss48.6.1

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Direct root Logins Not Allowed
  copy:
    dest: /etc/securetty
    content: ''
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27294-8
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-2
  - PCI-DSSv4-8.6.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_direct_root_logins
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

echo > /etc/securetty

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,
        mode: 0600
        path: /etc/securetty
        overwrite: true

Rule   Restrict Serial Port Root Logins   [ref]

To restrict root logins on serial ports, ensure lines of this form do not appear in /etc/securetty: 
ttyS0
ttyS1
Rationale:
Preventing direct root login to serial port interfaces helps ensure accountability for actions taken on the systems using the root account.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_restrict_serial_port_logins
Identifiers:

CCE-27268-2

References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.1.1, 3.1.5
disaCCI-000770
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2
nistAC-6, CM-6(a)
nist-csfPR.AC-4, PR.DS-5

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Restrict Serial Port Root Logins
  lineinfile:
    dest: /etc/securetty
    regexp: ttyS[0-9]
    state: absent
  tags:
  - CCE-27268-2
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_serial_port_logins
  - restrict_strategy


sed -i '/ttyS/d' /etc/securetty
Group   GRUB2 bootloader configuration   Group contains 2 groups and 4 rules
[ref]   During the boot process, the boot loader is responsible for starting the execution of the kernel and passing options to it. The boot loader allows for the selection of different kernels - possibly on different partitions or media. The default Red Hat Enterprise Linux 7 boot loader for x86 systems is called GRUB2. Options it can pass to the kernel include single-user mode, which provides root access without any authentication, and the ability to disable SELinux. To prevent local users from modifying the boot parameters and endangering security, protect the boot loader configuration with a password and ensure its configuration file's permissions are set properly.
Group   Non-UEFI GRUB2 bootloader configuration   Group contains 3 rules
[ref]   Non-UEFI GRUB2 bootloader configuration

Rule   Verify /boot/grub2/grub.cfg Group Ownership   [ref]

The file /boot/grub2/grub.cfg should be group-owned by the root group to prevent destruction or modification of the file. To properly set the group owner of /boot/grub2/grub.cfg, run the command: 
$ sudo chgrp root /boot/grub2/grub.cfg
Rationale:
The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_grub2_cfg
Identifiers:

CCE-82023-3

References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.4.5
disaCCI-000225
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistCM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
pcidssReq-7.1
os-srgSRG-OS-000480-GPOS-00227
anssiR29
cis1.3.2
pcidss42.2.6

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-82023-3
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/grub.cfg
  stat:
    path: /boot/grub2/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-82023-3
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /boot/grub2/grub.cfg
  file:
    path: /boot/grub2/grub.cfg
    group: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CCE-82023-3
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -d /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chgrp 0 /boot/grub2/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/grub2/grub.cfg User Ownership   [ref]

The file /boot/grub2/grub.cfg should be owned by the root user to prevent destruction or modification of the file. To properly set the owner of /boot/grub2/grub.cfg, run the command: 
$ sudo chown root /boot/grub2/grub.cfg
Rationale:
Only root should be able to modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_grub2_cfg
Identifiers:

CCE-82026-6

References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.4.5
disaCCI-000225
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistCM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
pcidssReq-7.1
os-srgSRG-OS-000480-GPOS-00227
anssiR29
cis1.3.2
pcidss42.2.6

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-82026-6
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/grub.cfg
  stat:
    path: /boot/grub2/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-82026-6
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /boot/grub2/grub.cfg
  file:
    path: /boot/grub2/grub.cfg
    owner: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CCE-82026-6
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -d /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chown 0 /boot/grub2/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Set Boot Loader Password in grub2   [ref]

The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command: 
# grub2-setpassword
When prompted, enter the password that was selected.

Warning:  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Rationale:
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_grub2_password
Identifiers:

CCE-27309-4

References:
cis-csc1, 11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
cui3.4.5
disaCCI-000213
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
iso27001-2013A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistCM-6(a)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3
osppFIA_UAU.1
os-srgSRG-OS-000080-GPOS-00048
stigidRHEL-07-010482
anssiR5
cis1.3.1
stigrefSV-204438r744095_rule
Group   UEFI GRUB2 bootloader configuration   Group contains 1 rule
[ref]   UEFI GRUB2 bootloader configuration
Warning:  UEFI generally uses vfat file systems, which does not support Unix-style permissions managed by chmod command. In this case, in order to change file permissions for files within /boot/efi it is necessary to update the mount options in /etc/fstab file and reboot the system.

Rule   Set the UEFI Boot Loader Password   [ref]

The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command: 
# grub2-setpassword
When prompted, enter the password that was selected.

Warning:  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Rationale:
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_grub2_uefi_password
Identifiers:

CCE-80354-4

References:
cis-csc11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06
cui3.4.5
disaCCI-000213
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
iso27001-2013A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistCM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.PT-3
osppFIA_UAU.1
os-srgSRG-OS-000080-GPOS-00048
stigidRHEL-07-010491
anssiR5
cis1.3.1
stigrefSV-204440r744098_rule
Group   Configure Syslog   Group contains 1 group and 1 rule
[ref]   The syslog service has been the default Unix logging mechanism for many years. It has a number of downsides, including inconsistent log format, lack of authentication for received messages, and lack of authentication, encryption, or reliable transport for messages sent over a network. However, due to its long history, syslog is a de facto standard which is supported by almost all Unix applications.

In Red Hat Enterprise Linux 7, rsyslog has replaced ksyslogd as the syslog daemon of choice, and it includes some additional security features such as reliable, connection-oriented (i.e. TCP) transmission of logs, the option to log to database formats, and the encryption of log data en route to a central logging server. This section discusses how to configure rsyslog for best effect, and how to use tools provided with the system to maintain and monitor logs.
Group   Rsyslog Logs Sent To Remote Host   Group contains 1 rule
[ref]   If system logs are to be useful in detecting malicious activities, it is necessary to send logs to a remote server. An intruder who has compromised the root account on a system may delete the log entries which indicate that the system was attacked before they are seen by an administrator.

However, it is recommended that logs be stored on the local host in addition to being sent to the loghost, especially if rsyslog has been configured to use the UDP protocol to send messages over a network. UDP does not guarantee reliable delivery, and moderately busy sites will lose log messages occasionally, especially in periods of high traffic which may be the result of an attack. In addition, remote rsyslog messages are not authenticated in any way by default, so it is easy for an attacker to introduce spurious messages to the central log server. Also, some problems cause loss of network connectivity, which will prevent the sending of messages to the central server. For all of these reasons, it is better to store log messages both centrally and on each host, so that they can be correlated if necessary.

Rule   Ensure Logs Sent To Remote Host   [ref]

To configure rsyslog to send logs to a remote log server, open /etc/rsyslog.conf and read and understand the last section of the file, which describes the multiple directives necessary to activate remote logging. Along with these other directives, the system can be configured to forward its logs to a particular log server by adding or correcting one of the following lines, substituting logcollector appropriately. The choice of protocol depends on the environment of the system; although TCP and RELP provide more reliable message delivery, they may not be supported in all environments.
To use UDP for log message delivery: 
*.* @logcollector

To use TCP for log message delivery: 
*.* @@logcollector

To use RELP for log message delivery: 
*.* :omrelp:logcollector

There must be a resolvable DNS CNAME or Alias record set to "logcollector" for logs to be sent correctly to the centralized logging utility.
Warning:  It is important to configure queues in case the client is sending log messages to a remote server. If queues are not configured, the system will stop functioning when the connection to the remote server is not available. Please consult Rsyslog documentation for more information about configuration of queues. The example configuration which should go into /etc/rsyslog.conf can look like the following lines: 
$ActionQueueType LinkedList
$ActionQueueFileName queuefilename
$ActionQueueMaxDiskSpace 1g
$ActionQueueSaveOnShutdown on
$ActionResumeRetryCount -1
Rationale:
A log server (loghost) receives syslog messages from one or more systems. This data can be used as an additional log source in the event a system is compromised and its local logs are suspect. Forwarding log messages to a remote loghost also provides system administrators with a centralized place to view the status of multiple hosts within the enterprise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_remote_loghost
Identifiers:

CCE-27343-3

References:
cis-csc1, 13, 14, 15, 16, 2, 3, 5, 6
cobit5APO11.04, APO13.01, BAI03.05, BAI04.04, DSS05.04, DSS05.07, MEA02.01
disaCCI-000366, CCI-001348, CCI-000136, CCI-001851
hipaa164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(B), 164.308(a)(5)(ii)(C), 164.308(a)(6)(ii), 164.308(a)(8), 164.310(d)(2)(iii), 164.312(b), 164.314(a)(2)(i)(C), 164.314(a)(2)(iii)
isa-62443-20094.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 7.1, SR 7.2
ism0988, 1405
iso27001-2013A.12.1.3, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.17.2.1
nerc-cipCIP-003-8 R5.2, CIP-004-6 R3.3
nistCM-6(a), AU-4(1), AU-9(2)
nist-csfPR.DS-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000479-GPOS-00224, SRG-OS-000480-GPOS-00227, SRG-OS-000342-GPOS-00133
stigidRHEL-07-031000
anssiR71
stigrefSV-204574r917830_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value rsyslog_remote_loghost_address # promote to variable
  set_fact:
    rsyslog_remote_loghost_address: !!str logcollector
  tags:
    - always

- name: Set rsyslog remote loghost
  lineinfile:
    dest: /etc/rsyslog.conf
    regexp: ^\*\.\*
    line: '*.* @@{{ rsyslog_remote_loghost_address }}'
    create: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27343-3
  - DISA-STIG-RHEL-07-031000
  - NIST-800-53-AU-4(1)
  - NIST-800-53-AU-9(2)
  - NIST-800-53-CM-6(a)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - rsyslog_remote_loghost


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

rsyslog_remote_loghost_address='logcollector'


# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^\*\.\*")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "@@$rsyslog_remote_loghost_address"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^\*\.\*\\>" "/etc/rsyslog.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^\*\.\*\\>.*/$escaped_formatted_output/gi" "/etc/rsyslog.conf"
else
    if [[ -s "/etc/rsyslog.conf" ]] && [[ -n "$(tail -c 1 -- "/etc/rsyslog.conf" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/rsyslog.conf"
    fi
    cce="CCE-27343-3"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/rsyslog.conf" >> "/etc/rsyslog.conf"
    printf '%s\n' "$formatted_output" >> "/etc/rsyslog.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Network Configuration and Firewalls   Group contains 1 group and 1 rule
[ref]   Most systems must be connected to a network of some sort, and this brings with it the substantial risk of network attack. This section discusses the security impact of decisions about networking which must be made when configuring a system.

This section also discusses firewalls, network access controls, and other network security frameworks, which allow system-level rules to be written that can limit an attackers' ability to connect to your system. These rules can specify that network traffic should be allowed or denied from certain IP addresses, hosts, and networks. The rules can also specify which of the system's network services are available to particular hosts or networks.
Group   IPSec Support   Group contains 1 rule
[ref]   Support for Internet Protocol Security (IPsec) is provided with Libreswan.

Rule   Verify Any Configured IPSec Tunnel Connections   [ref]

Libreswan provides an implementation of IPsec and IKE, which permits the creation of secure tunnels over untrusted networks. As such, IPsec can be used to circumvent certain network requirements such as filtering. Verify that if any IPsec connection (conn) configured in /etc/ipsec.conf and /etc/ipsec.d exists is an approved organizational connection.
Warning:  Automatic remediation of this control is not available due to the unique requirements of each system.
Rationale:
IP tunneling mechanisms can be used to bypass network filtering.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_libreswan_approved_tunnels
Identifiers:

CCE-80171-2

References:
cis-csc1, 12, 13, 14, 15, 16, 18, 4, 6, 8, 9
cobit5APO01.06, APO13.01, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.07, DSS06.02
disaCCI-000336
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.2.3.4, 4.3.3.4, 4.4.3.3
isa-62443-2013SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.1, A.12.1.2, A.13.1.1, A.13.1.2, A.13.1.3, A.13.2.1, A.13.2.2, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistAC-17(a), MA-4(6), CM-6(a), AC-4, SC-8
nist-csfDE.AE-1, ID.AM-3, PR.AC-5, PR.DS-5, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
stigidRHEL-07-040820
stigrefSV-204629r603261_rule
Group   File Permissions and Masks   Group contains 4 groups and 6 rules
[ref]   Traditional Unix security relies heavily on file and directory permissions to prevent unauthorized users from reading or modifying files to which they should not have access.

Several of the commands in this section search filesystems for files or directories with certain characteristics, and are intended to be run on every local partition on a given system. When the variable PART appears in one of the commands below, it means that the command is intended to be run repeatedly, with the name of each local partition substituted for PART in turn.

The following command prints a list of all xfs partitions on the local system, which is the default filesystem for Red Hat Enterprise Linux 7 installations: 
$ mount -t xfs | awk '{print $3}'
For any systems that use a different local filesystem type, modify this command as appropriate.
Group   Restrict Dynamic Mounting and Unmounting of Filesystems   Group contains 2 rules
[ref]   Linux includes a number of facilities for the automated addition and removal of filesystems on a running system. These facilities may be necessary in many environments, but this capability also carries some risk -- whether direct risk from allowing users to introduce arbitrary filesystems, or risk that software flaws in the automated mount facility itself could allow an attacker to compromise the system.

This command can be used to list the types of filesystems that are available to the currently executing kernel: 
$ find /lib/modules/`uname -r`/kernel/fs -type f -name '*.ko'
If these filesystems are not required then they can be explicitly disabled in a configuratio file in /etc/modprobe.d.

Rule   Disable the Automounter   [ref]

The autofs daemon mounts and unmounts filesystems, such as user home directories shared via NFS, on demand. In addition, autofs can be used to handle removable media, and the default configuration provides the cdrom device as /misc/cd. However, this method of providing access to removable media is not common, so autofs can almost always be disabled if NFS is not in use. Even if NFS is required, it may be possible to configure filesystem mounts statically by editing /etc/fstab rather than relying on the automounter.

The autofs service can be disabled with the following command: 
$ sudo systemctl mask --now autofs.service
Rationale:
Disabling the automounter permits the administrator to statically control filesystem mounting through /etc/fstab.

Additionally, automatically mounting filesystems permits easy introduction of unknown devices, thereby facilitating malicious activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_autofs_disabled
Identifiers:

CCE-27498-5

References:
cis-csc1, 12, 15, 16, 5
cobit5APO13.01, DSS01.04, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.4.6
disaCCI-000366, CCI-000778, CCI-001958
hipaa164.308(a)(3)(i), 164.308(a)(3)(ii)(A), 164.310(d)(1), 164.310(d)(2), 164.312(a)(1), 164.312(a)(2)(iv), 164.312(b)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.6
iso27001-2013A.11.2.6, A.13.1.1, A.13.2.1, A.18.1.4, A.6.2.1, A.6.2.2, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nistCM-7(a), CM-7(b), CM-6(a), MP-7
nist-csfPR.AC-1, PR.AC-3, PR.AC-6, PR.AC-7
os-srgSRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227
stigidRHEL-07-020110
cis2.2.1
stigrefSV-204451r853893_rule


[customizations.services]
masked = ["autofs"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27498-5
  - DISA-STIG-RHEL-07-020110
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Disable the Automounter - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman",
    "container"] and "autofs" in ansible_facts.packages )
  tags:
  - CCE-27498-5
  - DISA-STIG-RHEL-07-020110
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Disable the Automounter - Ensure autofs.service is Masked
  ansible.builtin.systemd:
    name: autofs.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    and "autofs" in ansible_facts.packages )
  - service_exists.stdout_lines is search("autofs.service", multiline=True)
  tags:
  - CCE-27498-5
  - DISA-STIG-RHEL-07-020110
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Unit Socket Exists - autofs.socket
  ansible.builtin.command: systemctl -q list-unit-files autofs.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman",
    "container"] and "autofs" in ansible_facts.packages )
  tags:
  - CCE-27498-5
  - DISA-STIG-RHEL-07-020110
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Disable the Automounter - Disable Socket autofs
  ansible.builtin.systemd:
    name: autofs.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    and "autofs" in ansible_facts.packages )
  - socket_file_exists.stdout_lines is search("autofs.socket", multiline=True)
  tags:
  - CCE-27498-5
  - DISA-STIG-RHEL-07-020110
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_autofs

class disable_autofs {
  service {'autofs':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q autofs ); then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'autofs.service'
"$SYSTEMCTL_EXEC" disable 'autofs.service'
"$SYSTEMCTL_EXEC" mask 'autofs.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files autofs.socket; then
    "$SYSTEMCTL_EXEC" stop 'autofs.socket'
    "$SYSTEMCTL_EXEC" mask 'autofs.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'autofs.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: autofs.service
        enabled: false
        mask: true
      - name: autofs.socket
        enabled: false
        mask: true

Rule   Disable Modprobe Loading of USB Storage Driver   [ref]

To prevent USB storage devices from being used, configure the kernel module loading system to prevent automatic loading of the USB storage driver. To configure the system to prevent the usb-storage kernel module from being loaded, add the following line to the file /etc/modprobe.d/usb-storage.conf: 
install usb-storage /bin/true
To configure the system to prevent the usb-storage from being used, add the following line to file /etc/modprobe.d/usb-storage.conf: 
blacklist usb-storage
This will prevent the modprobe program from loading the usb-storage module, but will not prevent an administrator (or another program) from using the insmod program to load the module manually.
Rationale:
USB storage devices such as thumb drives can be used to introduce malicious software.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_kernel_module_usb-storage_disabled
Identifiers:

CCE-27277-3

References:
cis-csc1, 12, 15, 16, 5
cobit5APO13.01, DSS01.04, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.1.21
disaCCI-000366, CCI-000778, CCI-001958
hipaa164.308(a)(3)(i), 164.308(a)(3)(ii)(A), 164.310(d)(1), 164.310(d)(2), 164.312(a)(1), 164.312(a)(2)(iv), 164.312(b)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.6
iso27001-2013A.11.2.6, A.13.1.1, A.13.2.1, A.18.1.4, A.6.2.1, A.6.2.2, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nistCM-7(a), CM-7(b), CM-6(a), MP-7
nist-csfPR.AC-1, PR.AC-3, PR.AC-6, PR.AC-7
os-srgSRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227
app-srg-ctrSRG-APP-000141-CTR-000315
stigidRHEL-07-020100
cis1.1.1.8
pcidss43.4.2
stigrefSV-204449r942894_rule

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Ensure kernel module 'usb-storage' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/usb-storage.conf
    regexp: install\s+usb-storage
    line: install usb-storage /bin/false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27277-3
  - DISA-STIG-RHEL-07-020100
  - NIST-800-171-3.1.21
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - PCI-DSSv4-3.4.2
  - disable_strategy
  - kernel_module_usb-storage_disabled
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required

- name: Ensure kernel module 'usb-storage' is blacklisted
  lineinfile:
    create: true
    dest: /etc/modprobe.d/usb-storage.conf
    regexp: ^blacklist usb-storage$
    line: blacklist usb-storage
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27277-3
  - DISA-STIG-RHEL-07-020100
  - NIST-800-171-3.1.21
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - PCI-DSSv4-3.4.2
  - disable_strategy
  - kernel_module_usb-storage_disabled
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if LC_ALL=C grep -q -m 1 "^install usb-storage" /etc/modprobe.d/usb-storage.conf ; then
	
	sed -i 's#^install usb-storage.*#install usb-storage /bin/false#g' /etc/modprobe.d/usb-storage.conf
else
	echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/usb-storage.conf
	echo "install usb-storage /bin/false" >> /etc/modprobe.d/usb-storage.conf
fi

if ! LC_ALL=C grep -q -m 1 "^blacklist usb-storage$" /etc/modprobe.d/usb-storage.conf ; then
	echo "blacklist usb-storage" >> /etc/modprobe.d/usb-storage.conf
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,install%20usb-storage%20/bin/false%0Ablacklist%20usb-storage%0A
        mode: 0644
        path: /etc/modprobe.d/usb-storage.conf
        overwrite: true
Group   Restrict Programs from Dangerous Execution Patterns   Group contains 2 groups and 4 rules
[ref]   The recommendations in this section are designed to ensure that the system's features to protect against potentially dangerous program execution are activated. These protections are applied at the system initialization or kernel level, and defend against certain types of badly-configured or compromised programs.
Group   Disable Core Dumps   Group contains 1 rule
[ref]   A core dump file is the memory image of an executable program when it was terminated by the operating system due to errant behavior. In most cases, only software developers legitimately need to access these files. The core dump files may also contain sensitive information, or unnecessarily occupy large amounts of disk space.

Once a hard limit is set in /etc/security/limits.conf, or to a file within the /etc/security/limits.d/ directory, a user cannot increase that limit within his or her own session. If access to core dumps is required, consider restricting them to only certain users or groups. See the limits.conf man page for more information.

The core dumps of setuid programs are further protected. The sysctl variable fs.suid_dumpable controls whether the kernel allows core dumps from these programs at all. The default value of 0 is recommended.

Rule   Disable Core Dumps for SUID programs   [ref]

To set the runtime status of the fs.suid_dumpable kernel parameter, run the following command: 
$ sudo sysctl -w fs.suid_dumpable=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d: 
fs.suid_dumpable = 0
Rationale:
The core dump of a setuid program is more likely to contain sensitive data, as the program itself runs with greater privileges than the user who initiated execution of the program. Disabling the ability for any setuid program to write a core file decreases the risk of unauthorized access of such data.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_fs_suid_dumpable
Identifiers:

CCE-26900-1

References:
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
nistSI-11(a), SI-11(b)
anssiR14
pcidss43.3.1.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    contains: ^[\s]*fs.suid_dumpable.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-26900-1
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Comment out any occurrences of fs.suid_dumpable from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*fs.suid_dumpable
    replace: '#fs.suid_dumpable'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-26900-1
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Ensure sysctl fs.suid_dumpable is set to 0
  sysctl:
    name: fs.suid_dumpable
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-26900-1
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of fs.suid_dumpable from /etc/sysctl.d/*.conf files

for f in /etc/sysctl.d/*.conf /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf; do


  # skip systemd-sysctl symlink (/etc/sysctl.d/99-sysctl.conf -> /etc/sysctl.conf)
  if [[ "$(readlink -f "$f")" == "/etc/sysctl.conf" ]]; then continue; fi

  matching_list=$(grep -P '^(?!#).*[\s]*fs.suid_dumpable.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "fs.suid_dumpable" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set sysctl config file which to save the desired value
#

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for fs.suid_dumpable
#
/sbin/sysctl -q -n -w fs.suid_dumpable="0"

#
# If fs.suid_dumpable present in /etc/sysctl.conf, change value to "0"
#	else, add "fs.suid_dumpable = 0" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^fs.suid_dumpable")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "0"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^fs.suid_dumpable\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^fs.suid_dumpable\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    cce="CCE-26900-1"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "${SYSCONFIG_FILE}" >> "${SYSCONFIG_FILE}"
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Enable ExecShield   Group contains 2 rules
[ref]   ExecShield describes kernel features that provide protection against exploitation of memory corruption errors such as buffer overflows. These features include random placement of the stack and other memory regions, prevention of execution in memory that should only hold data, and special handling of text buffers. These protections are enabled by default on 32-bit systems and controlled through sysctl variables kernel.exec-shield and kernel.randomize_va_space. On the latest 64-bit systems, kernel.exec-shield cannot be enabled or disabled with sysctl.

Rule   Enable ExecShield via sysctl   [ref]

By default on Red Hat Enterprise Linux 7 64-bit systems, ExecShield is enabled and can only be disabled if the hardware does not support ExecShield or is disabled in /etc/default/grub.
Rationale:
ExecShield uses the segmentation feature on all x86 systems to prevent execution in memory higher than a certain address. It writes an address as a limit in the code segment descriptor, to control where code can be executed, on a per-process basis. When the kernel places a process's memory regions such as the stack and heap higher than this address, the hardware prevents execution in that address range. This is enabled by default on the latest Red Hat and Fedora systems if supported by the hardware.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_kernel_exec_shield
Identifiers:

CCE-27211-2

References:
cis-csc12, 15, 8
cobit5APO13.01, DSS05.02
cui3.1.7
disaCCI-002530
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
isa-62443-2013SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.13.1.1, A.13.2.1, A.14.1.3
nistSC-39, CM-6(a)
nist-csfPR.PT-4
os-srgSRG-OS-000433-GPOS-00192

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Check noexec argument exists
  command: grep '^GRUB_CMDLINE_LINUX=.*noexec=.*"' /etc/default/grub
  failed_when: false
  register: argcheck
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27211-2
  - NIST-800-171-3.1.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy
  - sysctl_kernel_exec_shield

- name: Replace existing noexec argument
  replace:
    path: /etc/default/grub
    regexp: \(^GRUB_CMDLINE_LINUX=".*\)noexec=?[^[:space:]]*\(.*"\)
    replace: \1 \2
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - argcheck is not skipped and argcheck.rc == 0
  tags:
  - CCE-27211-2
  - NIST-800-171-3.1.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy
  - sysctl_kernel_exec_shield

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --remove-args="noexec"
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27211-2
  - NIST-800-171-3.1.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy
  - sysctl_kernel_exec_shield

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Correct the form of default kernel command line in GRUB
if grep -q '^GRUB_CMDLINE_LINUX=.*noexec=.*"'  '/etc/default/grub' ; then
       sed -i 's/\(^GRUB_CMDLINE_LINUX=".*\)noexec=?[^[:space:]]*\(.*"\)/\1 \2/' '/etc/default/grub'
fi
grubby --update-kernel=ALL --remove-args=noexec

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Enable Randomized Layout of Virtual Address Space   [ref]

To set the runtime status of the kernel.randomize_va_space kernel parameter, run the following command: 
$ sudo sysctl -w kernel.randomize_va_space=2
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d: 
kernel.randomize_va_space = 2
Rationale:
Address space layout randomization (ASLR) makes it more difficult for an attacker to predict the location of attack code they have introduced into a process's address space during an attempt at exploitation. Additionally, ASLR makes it more difficult for an attacker to know the location of existing code in order to re-purpose it using return oriented programming (ROP) techniques.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_kernel_randomize_va_space
Identifiers:

CCE-27127-0

References:
cui3.1.7
disaCCI-000366, CCI-002824
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
nerc-cipCIP-002-5 R1.1, CIP-002-5 R1.2, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 4.1, CIP-004-6 4.2, CIP-004-6 R2.2.3, CIP-004-6 R2.2.4, CIP-004-6 R2.3, CIP-004-6 R4, CIP-005-6 R1, CIP-005-6 R1.1, CIP-005-6 R1.2, CIP-007-3 R3, CIP-007-3 R3.1, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, CIP-007-3 R8.4, CIP-009-6 R.1.1, CIP-009-6 R4
nistSC-30, SC-30(2), CM-6(a)
pcidssReq-2.2.1
os-srgSRG-OS-000433-GPOS-00193, SRG-OS-000480-GPOS-00227
app-srg-ctrSRG-APP-000450-CTR-001105
stigidRHEL-07-040201
anssiR9
cis1.4.1
pcidss43.3.1.1
stigrefSV-204584r880794_rule

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    contains: ^[\s]*kernel.randomize_va_space.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27127-0
  - DISA-STIG-RHEL-07-040201
  - NIST-800-171-3.1.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-30
  - NIST-800-53-SC-30(2)
  - PCI-DSS-Req-2.2.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_randomize_va_space

- name: Comment out any occurrences of kernel.randomize_va_space from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*kernel.randomize_va_space
    replace: '#kernel.randomize_va_space'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27127-0
  - DISA-STIG-RHEL-07-040201
  - NIST-800-171-3.1.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-30
  - NIST-800-53-SC-30(2)
  - PCI-DSS-Req-2.2.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_randomize_va_space

- name: Ensure sysctl kernel.randomize_va_space is set to 2
  sysctl:
    name: kernel.randomize_va_space
    value: '2'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27127-0
  - DISA-STIG-RHEL-07-040201
  - NIST-800-171-3.1.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-30
  - NIST-800-53-SC-30(2)
  - PCI-DSS-Req-2.2.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_randomize_va_space

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.randomize_va_space from /etc/sysctl.d/*.conf files

for f in /etc/sysctl.d/*.conf /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf; do


  # skip systemd-sysctl symlink (/etc/sysctl.d/99-sysctl.conf -> /etc/sysctl.conf)
  if [[ "$(readlink -f "$f")" == "/etc/sysctl.conf" ]]; then continue; fi

  matching_list=$(grep -P '^(?!#).*[\s]*kernel.randomize_va_space.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "kernel.randomize_va_space" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set sysctl config file which to save the desired value
#

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for kernel.randomize_va_space
#
/sbin/sysctl -q -n -w kernel.randomize_va_space="2"

#
# If kernel.randomize_va_space present in /etc/sysctl.conf, change value to "2"
#	else, add "kernel.randomize_va_space = 2" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.randomize_va_space")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "2"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.randomize_va_space\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^kernel.randomize_va_space\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    cce="CCE-27127-0"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "${SYSCONFIG_FILE}" >> "${SYSCONFIG_FILE}"
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.randomize_va_space%3D2%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_randomize_va_space.conf
        overwrite: true

Rule   Restrict Access to Kernel Message Buffer   [ref]

To set the runtime status of the kernel.dmesg_restrict kernel parameter, run the following command: 
$ sudo sysctl -w kernel.dmesg_restrict=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d: 
kernel.dmesg_restrict = 1
Rationale:
Unprivileged access to the kernel syslog can expose sensitive kernel address information.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_kernel_dmesg_restrict
Identifiers:

CCE-27050-4

References:
cui3.1.5
disaCCI-001090, CCI-001314
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
nistSI-11(a), SI-11(b)
os-srgSRG-OS-000132-GPOS-00067, SRG-OS-000138-GPOS-00069
app-srg-ctrSRG-APP-000243-CTR-000600
stigidRHEL-07-010375
anssiR9
stigrefSV-255927r880791_rule

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    contains: ^[\s]*kernel.dmesg_restrict.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27050-4
  - DISA-STIG-RHEL-07-010375
  - NIST-800-171-3.1.5
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - disable_strategy
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required
  - sysctl_kernel_dmesg_restrict

- name: Comment out any occurrences of kernel.dmesg_restrict from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*kernel.dmesg_restrict
    replace: '#kernel.dmesg_restrict'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27050-4
  - DISA-STIG-RHEL-07-010375
  - NIST-800-171-3.1.5
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - disable_strategy
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required
  - sysctl_kernel_dmesg_restrict

- name: Ensure sysctl kernel.dmesg_restrict is set to 1
  sysctl:
    name: kernel.dmesg_restrict
    value: '1'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27050-4
  - DISA-STIG-RHEL-07-010375
  - NIST-800-171-3.1.5
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - disable_strategy
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required
  - sysctl_kernel_dmesg_restrict

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of kernel.dmesg_restrict from /etc/sysctl.d/*.conf files

for f in /etc/sysctl.d/*.conf /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf; do


  # skip systemd-sysctl symlink (/etc/sysctl.d/99-sysctl.conf -> /etc/sysctl.conf)
  if [[ "$(readlink -f "$f")" == "/etc/sysctl.conf" ]]; then continue; fi

  matching_list=$(grep -P '^(?!#).*[\s]*kernel.dmesg_restrict.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "kernel.dmesg_restrict" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set sysctl config file which to save the desired value
#

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for kernel.dmesg_restrict
#
/sbin/sysctl -q -n -w kernel.dmesg_restrict="1"

#
# If kernel.dmesg_restrict present in /etc/sysctl.conf, change value to "1"
#	else, add "kernel.dmesg_restrict = 1" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^kernel.dmesg_restrict")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^kernel.dmesg_restrict\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^kernel.dmesg_restrict\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    cce="CCE-27050-4"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "${SYSCONFIG_FILE}" >> "${SYSCONFIG_FILE}"
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,kernel.dmesg_restrict%3D1%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_kernel_dmesg_restrict.conf
        overwrite: true
Group   SELinux   Group contains 1 group and 7 rules
[ref]   SELinux is a feature of the Linux kernel which can be used to guard against misconfigured or compromised programs. SELinux enforces the idea that programs should be limited in what files they can access and what actions they can take.

The default SELinux policy, as configured on Red Hat Enterprise Linux 7, has been sufficiently developed and debugged that it should be usable on almost any system with minimal configuration and a small amount of system administrator training. This policy prevents system services - including most of the common network-visible services such as mail servers, FTP servers, and DNS servers - from accessing files which those services have no valid reason to access. This action alone prevents a huge amount of possible damage from network attacks against services, from trojaned software, and so forth.

This guide recommends that SELinux be enabled using the default (targeted) policy on every Red Hat Enterprise Linux 7 system, unless that system has unusual requirements which make a stronger policy appropriate.

For more information on SELinux, see https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/selinux_users_and_administrators_guide.
Group   SELinux - Booleans   Group contains 3 rules
[ref]   Enable or Disable runtime customization of SELinux system policies without having to reload or recompile the SELinux policy.

Rule   Disable the selinuxuser_execheap SELinux Boolean   [ref]

By default, the SELinux boolean selinuxuser_execheap is disabled. When enabled this boolean is enabled it allows selinuxusers to execute code from the heap. If this setting is enabled, it should be disabled. To disable the selinuxuser_execheap SELinux boolean, run the following command: 
$ sudo setsebool -P selinuxuser_execheap off
Rationale:
Disabling code execution from the heap blocks buffer overflow attacks.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sebool_selinuxuser_execheap
Identifiers:

CCE-82312-0

References:
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
anssiR48

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Disable the selinuxuser_execheap SELinux Boolean - Ensure libsemanage-python
    Installed
  package:
    name: libsemanage-python
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-82312-0
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - sebool_selinuxuser_execheap
- name: XCCDF Value var_selinuxuser_execheap # promote to variable
  set_fact:
    var_selinuxuser_execheap: !!str false
  tags:
    - always

- name: Disable the selinuxuser_execheap SELinux Boolean - Set SELinux Boolean selinuxuser_execheap
    Accordingly
  seboolean:
    name: selinuxuser_execheap
    state: '{{ var_selinuxuser_execheap }}'
    persistent: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_facts.selinux.status == 'enabled'
  tags:
  - CCE-82312-0
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - sebool_selinuxuser_execheap

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "libsemanage-python" ; then
    yum install -y "libsemanage-python"
fi


if selinuxenabled; then

    var_selinuxuser_execheap='false'

    setsebool -P selinuxuser_execheap $var_selinuxuser_execheap

else
    echo "Skipping remediation, SELinux is disabled";
    false
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Enable the selinuxuser_execmod SELinux Boolean   [ref]

By default, the SELinux boolean selinuxuser_execmod is enabled. If this setting is disabled, it should be enabled. To enable the selinuxuser_execmod SELinux boolean, run the following command: 
$ sudo setsebool -P selinuxuser_execmod on
Rationale:
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sebool_selinuxuser_execmod
Identifiers:

CCE-82313-8

References:
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Enable the selinuxuser_execmod SELinux Boolean - Ensure libsemanage-python
    Installed
  package:
    name: libsemanage-python
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-82313-8
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - sebool_selinuxuser_execmod
- name: XCCDF Value var_selinuxuser_execmod # promote to variable
  set_fact:
    var_selinuxuser_execmod: !!str true
  tags:
    - always

- name: Enable the selinuxuser_execmod SELinux Boolean - Set SELinux Boolean selinuxuser_execmod
    Accordingly
  seboolean:
    name: selinuxuser_execmod
    state: '{{ var_selinuxuser_execmod }}'
    persistent: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_facts.selinux.status == 'enabled'
  tags:
  - CCE-82313-8
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - sebool_selinuxuser_execmod

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "libsemanage-python" ; then
    yum install -y "libsemanage-python"
fi


if selinuxenabled; then

    var_selinuxuser_execmod='true'

    setsebool -P selinuxuser_execmod $var_selinuxuser_execmod

else
    echo "Skipping remediation, SELinux is disabled";
    false
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable the selinuxuser_execstack SELinux Boolean   [ref]

By default, the SELinux boolean selinuxuser_execstack is enabled. This setting should be disabled as unconfined executables should not be able to make their stack executable. To disable the selinuxuser_execstack SELinux boolean, run the following command: 
$ sudo setsebool -P selinuxuser_execstack off
Rationale:
Disabling code execution from the stack blocks buffer overflow attacks.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sebool_selinuxuser_execstack
Identifiers:

CCE-82314-6

References:
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
anssiR48

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Disable the selinuxuser_execstack SELinux Boolean - Ensure libsemanage-python
    Installed
  package:
    name: libsemanage-python
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-82314-6
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - sebool_selinuxuser_execstack
- name: XCCDF Value var_selinuxuser_execstack # promote to variable
  set_fact:
    var_selinuxuser_execstack: !!str false
  tags:
    - always

- name: Disable the selinuxuser_execstack SELinux Boolean - Set SELinux Boolean selinuxuser_execstack
    Accordingly
  seboolean:
    name: selinuxuser_execstack
    state: '{{ var_selinuxuser_execstack }}'
    persistent: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_facts.selinux.status == 'enabled'
  tags:
  - CCE-82314-6
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - sebool_selinuxuser_execstack

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "libsemanage-python" ; then
    yum install -y "libsemanage-python"
fi


if selinuxenabled; then

    var_selinuxuser_execstack='false'

    setsebool -P selinuxuser_execstack $var_selinuxuser_execstack

else
    echo "Skipping remediation, SELinux is disabled";
    false
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure SELinux Not Disabled in /etc/default/grub   [ref]

SELinux can be disabled at boot time by an argument in /etc/default/grub. Remove any instances of selinux=0 from the kernel arguments in that file to prevent SELinux from being disabled at boot.
Rationale:
Disabling a major host protection feature, such as SELinux, at boot time prevents it from confining system services at boot time. Further, it increases the chances that it will remain off during system operation.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_grub2_enable_selinux
Identifiers:

CCE-26961-3

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 4, 5, 6, 8, 9
cobit5APO01.06, APO11.04, APO13.01, BAI03.05, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06, MEA02.01
cui3.1.2, 3.7.2
disaCCI-000022, CCI-000032
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
isa-62443-20094.2.3.4, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.4, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, 4.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.2, A.13.1.3, A.13.2.1, A.13.2.2, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3
nistAC-3, AC-3(3)(a)
nist-csfDE.AE-1, ID.AM-3, PR.AC-4, PR.AC-5, PR.AC-6, PR.DS-5, PR.PT-1, PR.PT-3, PR.PT-4
cis1.5.1.2
pcidss41.2.6

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure SELinux Not Disabled in /etc/default/grub - Find /etc/grub.d/ files
  ansible.builtin.find:
    paths:
    - /etc/grub.d/
    follow: true
  register: result_grub_d
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure SELinux Not Disabled in /etc/default/grub - Ensure SELinux Not Disabled
    in /etc/grub.d/ files
  ansible.builtin.replace:
    dest: '{{ item.path }}'
    regexp: (selinux|enforcing)=0
  with_items:
  - '{{ result_grub_d.files }}'
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure SELinux Not Disabled in /etc/default/grub - Check if /etc/grub2.cfg
    exists
  ansible.builtin.stat:
    path: /etc/grub2.cfg
  register: result_grub2_cfg_present
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure SELinux Not Disabled in /etc/default/grub - Check if /etc/default/grub
    exists
  ansible.builtin.stat:
    path: /etc/default/grub
  register: result_default_grub_present
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure SELinux Not Disabled in /etc/default/grub - Ensure SELinux Not Disabled
    in /etc/grub2.cfg
  ansible.builtin.replace:
    dest: /etc/grub2.cfg
    regexp: (selinux|enforcing)=0
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  - result_grub2_cfg_present.stat.exists
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure SELinux Not Disabled in /etc/default/grub - Ensure SELinux Not Disabled
    in /etc/default/grub
  ansible.builtin.replace:
    dest: /etc/default/grub
    regexp: (selinux|enforcing)=0
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  - result_default_grub_present.stat.exists
  tags:
  - CCE-26961-3
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - PCI-DSSv4-1.2.6
  - grub2_enable_selinux
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

sed -i --follow-symlinks "s/selinux=0//gI" /etc/default/grub /etc/grub2.cfg /etc/grub.d/*
sed -i --follow-symlinks "s/enforcing=0//gI" /etc/default/grub /etc/grub2.cfg /etc/grub.d/*

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure No Daemons are Unconfined by SELinux   [ref]

Daemons for which the SELinux policy does not contain rules will inherit the context of the parent process. Because daemons are launched during startup and descend from the init process, they inherit the unconfined_service_t context.

To check for unconfined daemons, run the following command: 
$ sudo ps -eZ | grep "unconfined_service_t"
It should produce no output in a well-configured system.
Warning:  Automatic remediation of this control is not available. Remediation can be achieved by amending SELinux policy or stopping the unconfined daemons as outlined above.
Rationale:
Daemons which run with the unconfined_service_t context may cause AVC denials, or allow privileges that the daemon does not require.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_selinux_confinement_of_daemons
Identifiers:

CCE-27288-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 5, 6, 9
cobit5APO01.06, APO11.04, BAI03.05, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06, MEA02.01
cui3.1.2, 3.1.5, 3.7.2
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
isa-62443-20094.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 5.2, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.5.1, A.12.6.2, A.12.7.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2
nistCM-7(a), CM-7(b), CM-6(a), AC-3(3)(a), AC-6
nist-csfPR.AC-4, PR.DS-5, PR.IP-1, PR.PT-1, PR.PT-3
cis1.5.1.6
pcidss41.2.6

Rule   Configure SELinux Policy   [ref]

The SELinux targeted policy is appropriate for general-purpose desktops and servers, as well as systems in many other roles. To configure the system to use this policy, add or correct the following line in /etc/selinux/config: 
SELINUXTYPE=targeted
Other policies, such as mls, provide additional security labeling and greater confinement but are not compatible with many general-purpose use cases.
Rationale:
Setting the SELinux policy to targeted or a more specialized policy ensures the system will confine processes that are likely to be targeted for exploitation, such as network or system services.

Note: During the development or debugging of SELinux modules, it is common to temporarily place non-production systems in permissive mode. In such temporary cases, SELinux policies should be developed, and once work is completed, the system should be reconfigured to targeted.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_selinux_policytype
Identifiers:

CCE-27279-9

References:
bsiAPP.4.4.A4
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 4, 5, 6, 8, 9
cobit5APO01.06, APO11.04, APO13.01, BAI03.05, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06, MEA02.01
cui3.1.2, 3.7.2
disaCCI-002165, CCI-002696
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
isa-62443-20094.2.3.4, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.4, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, 4.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.2, A.13.1.3, A.13.2.1, A.13.2.2, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.2, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-004-6 R3.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, CIP-007-3 R6.5
nistAC-3, AC-3(3)(a), AU-9, SC-7(21)
nist-csfDE.AE-1, ID.AM-3, PR.AC-4, PR.AC-5, PR.AC-6, PR.DS-5, PR.PT-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000445-GPOS-00199
app-srg-ctrSRG-APP-000233-CTR-000585
stigidRHEL-07-020220
anssiR46, R64
cis1.5.1.3
pcidss41.2.6
stigrefSV-204454r942903_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: XCCDF Value var_selinux_policy_name # promote to variable
  set_fact:
    var_selinux_policy_name: !!str targeted
  tags:
    - always

- name: Configure SELinux Policy
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: ^SELINUXTYPE=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/selinux/config
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: ^SELINUXTYPE=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/selinux/config
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: ^SELINUXTYPE=
      line: SELINUXTYPE={{ var_selinux_policy_name }}
      state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27279-9
  - DISA-STIG-RHEL-07-020220
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - NIST-800-53-AU-9
  - NIST-800-53-SC-7(21)
  - PCI-DSSv4-1.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy
  - selinux_policytype

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

var_selinux_policy_name='targeted'


if [ -e "/etc/selinux/config" ] ; then
    
    LC_ALL=C sed -i "/^SELINUXTYPE=/Id" "/etc/selinux/config"
else
    touch "/etc/selinux/config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/selinux/config"

cp "/etc/selinux/config" "/etc/selinux/config.bak"
# Insert at the end of the file
printf '%s\n' "SELINUXTYPE=$var_selinux_policy_name" >> "/etc/selinux/config"
# Clean up after ourselves.
rm "/etc/selinux/config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure SELinux State is Enforcing   [ref]

The SELinux state should be set to enforcing at system boot time. In the file /etc/selinux/config, add or correct the following line to configure the system to boot into enforcing mode: 
SELINUX=enforcing
Rationale:
Setting the SELinux state to enforcing ensures SELinux is able to confine potentially compromised processes to the security policy, which is designed to prevent them from causing damage to the system or further elevating their privileges.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_selinux_state
Identifiers:

CCE-27334-2

References:
bsiAPP.4.4.A4
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 4, 5, 6, 8, 9
cobit5APO01.06, APO11.04, APO13.01, BAI03.05, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06, MEA02.01
cui3.1.2, 3.7.2
disaCCI-001084, CCI-002165, CCI-002696
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
isa-62443-20094.2.3.4, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.4, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, 4.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.1, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.2, A.13.1.3, A.13.2.1, A.13.2.2, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.2, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-004-6 R3.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, CIP-007-3 R6.5
nistAC-3, AC-3(3)(a), AU-9, SC-7(21)
nist-csfDE.AE-1, ID.AM-3, PR.AC-4, PR.AC-5, PR.AC-6, PR.DS-5, PR.PT-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000445-GPOS-00199, SRG-OS-000134-GPOS-00068
stigidRHEL-07-020210
anssiR37, R79
cis1.5.1.5
pcidss41.2.6
stigrefSV-204453r942900_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value var_selinux_state # promote to variable
  set_fact:
    var_selinux_state: !!str enforcing
  tags:
    - always

- name: Ensure SELinux State is Enforcing
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: ^SELINUX=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/selinux/config
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: ^SELINUX=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/selinux/config
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: ^SELINUX=
      line: SELINUX={{ var_selinux_state }}
      state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27334-2
  - DISA-STIG-RHEL-07-020210
  - NIST-800-171-3.1.2
  - NIST-800-171-3.7.2
  - NIST-800-53-AC-3
  - NIST-800-53-AC-3(3)(a)
  - NIST-800-53-AU-9
  - NIST-800-53-SC-7(21)
  - PCI-DSSv4-1.2.6
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy
  - selinux_state

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

var_selinux_state='enforcing'


if [ -e "/etc/selinux/config" ] ; then
    
    LC_ALL=C sed -i "/^SELINUX=/Id" "/etc/selinux/config"
else
    touch "/etc/selinux/config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/selinux/config"

cp "/etc/selinux/config" "/etc/selinux/config.bak"
# Insert at the end of the file
printf '%s\n' "SELINUX=$var_selinux_state" >> "/etc/selinux/config"
# Clean up after ourselves.
rm "/etc/selinux/config.bak"

fixfiles onboot
fixfiles -f relabel

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Services   Group contains 14 groups and 34 rules
[ref]   The best protection against vulnerable software is running less software. This section describes how to review the software which Red Hat Enterprise Linux 7 installs on a system and disable software which is not needed. It then enumerates the software packages installed on a default Red Hat Enterprise Linux 7 system and provides guidance about which ones can be safely disabled.

Red Hat Enterprise Linux 7 provides a convenient minimal install option that essentially installs the bare necessities for a functional system. When building Red Hat Enterprise Linux 7 systems, it is highly recommended to select the minimal packages and then build up the system from there.
Group   Base Services   Group contains 1 rule
[ref]   This section addresses the base services that are installed on a Red Hat Enterprise Linux 7 default installation which are not covered in other sections. Some of these services listen on the network and should be treated with particular discretion. Other services are local system utilities that may or may not be extraneous. In general, system services should be disabled if not required.

Rule   Disable KDump Kernel Crash Analyzer (kdump)   [ref]

The kdump service provides a kernel crash dump analyzer. It uses the kexec system call to boot a secondary kernel ("capture" kernel) following a system crash, which can load information from the crashed kernel for analysis. The kdump service can be disabled with the following command: 
$ sudo systemctl mask --now kdump.service
Rationale:
Kernel core dumps may contain the full contents of system memory at the time of the crash. Kernel core dumps consume a considerable amount of disk space and may result in denial of service by exhausting the available space on the target file system partition. Unless the system is used for kernel development or testing, there is little need to run the kdump service.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_kdump_disabled
Identifiers:

CCE-80258-7

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000366, CCI-001665
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
osppFMT_SMF_EXT.1.1
os-srgSRG-OS-000269-GPOS-00103, SRG-OS-000480-GPOS-00227
stigidRHEL-07-021300
stigrefSV-204492r603261_rule


[customizations.services]
masked = ["kdump"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable KDump Kernel Crash Analyzer (kdump) - Collect systemd Services Present
    in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80258-7
  - DISA-STIG-RHEL-07-021300
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_kdump_disabled

- name: Disable KDump Kernel Crash Analyzer (kdump) - Ensure kdump.service is Masked
  ansible.builtin.systemd:
    name: kdump.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("kdump.service", multiline=True)
  tags:
  - CCE-80258-7
  - DISA-STIG-RHEL-07-021300
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_kdump_disabled

- name: Unit Socket Exists - kdump.socket
  ansible.builtin.command: systemctl -q list-unit-files kdump.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80258-7
  - DISA-STIG-RHEL-07-021300
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_kdump_disabled

- name: Disable KDump Kernel Crash Analyzer (kdump) - Disable Socket kdump
  ansible.builtin.systemd:
    name: kdump.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("kdump.socket", multiline=True)
  tags:
  - CCE-80258-7
  - DISA-STIG-RHEL-07-021300
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_kdump_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_kdump

class disable_kdump {
  service {'kdump':
    enable => false,
    ensure => 'stopped',
  }
}



kdump --disable

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'kdump.service'
"$SYSTEMCTL_EXEC" disable 'kdump.service'
"$SYSTEMCTL_EXEC" mask 'kdump.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files kdump.socket; then
    "$SYSTEMCTL_EXEC" stop 'kdump.socket'
    "$SYSTEMCTL_EXEC" mask 'kdump.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'kdump.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: kdump.service
        enabled: false
        mask: true
      - name: kdump.socket
        enabled: false
        mask: true
Group   Cron and At Daemons   Group contains 1 rule
[ref]   The cron and at services are used to allow commands to be executed at a later time. The cron service is required by almost all systems to perform necessary maintenance tasks, while at may or may not be required on a given system. Both daemons should be configured defensively.

Rule   Enable cron Service   [ref]

The crond service is used to execute commands at preconfigured times. It is required by almost all systems to perform necessary maintenance tasks, such as notifying root of system activity. The crond service can be enabled with the following command: 
$ sudo systemctl enable crond.service
Rationale:
Due to its usage for maintenance and security-supporting tasks, enabling the cron daemon is essential.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_crond_enabled
Identifiers:

CCE-27323-5

References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.9.1.2
nistCM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis4.1.1.1


[customizations.services]
enabled = ["crond"]

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Enable cron Service - Enable service crond
  block:

  - name: Gather the package facts
    package_facts:
      manager: auto

  - name: Enable cron Service - Enable Service crond
    ansible.builtin.systemd:
      name: crond
      enabled: true
      state: started
      masked: false
    when:
    - '"cronie" in ansible_facts.packages'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27323-5
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_crond_enabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include enable_crond

class enable_crond {
  service {'crond':
    enable => true,
    ensure => 'running',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'crond.service'
"$SYSTEMCTL_EXEC" start 'crond.service'
"$SYSTEMCTL_EXEC" enable 'crond.service'

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   NFS and RPC   Group contains 1 group and 1 rule
[ref]   The Network File System is a popular distributed filesystem for the Unix environment, and is very widely deployed. This section discusses the circumstances under which it is possible to disable NFS and its dependencies, and then details steps which should be taken to secure NFS's configuration. This section is relevant to systems operating as NFS clients, as well as to those operating as NFS servers.
Group   Configure NFS Servers   Group contains 1 rule
[ref]   The steps in this section are appropriate for systems which operate as NFS servers.

Rule   Use Kerberos Security on All Exports   [ref]

Using Kerberos on all exported mounts prevents a malicious client or user from impersonating a system user. To cryptography authenticate users to the NFS server, add sec=krb5:krb5i:krb5p to each export in /etc/exports.
Rationale:
When an NFS server is configured to use AUTH_SYS a selected userid and groupid are used to handle requests from the remote user. The userid and groupid could mistakenly or maliciously be set incorrectly. The AUTH_GSS method of authentication uses certificates on the server and client systems to more securely authenticate the remote mount request.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_use_kerberos_security_all_exports
Identifiers:

CCE-27464-7

References:
cis-csc1, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.04, DSS05.10, DSS06.10
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1
iso27001-2013A.18.1.4, A.6.1.2, A.9.1.2, A.9.2.1, A.9.2.3, A.9.2.4, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistCM-7(a), CM-7(b), CM-6(a), IA-2, IA-2(8), IA-2(9), AC-17(a)
nist-csfPR.AC-4, PR.AC-7
os-srgSRG-OS-000480-GPOS-00227

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Drop any security clause for every export
  replace:
    path: /etc/exports
    regexp: ^(/.*\w+.*\(.*),sec=[^,]*(.*\)\w*$)
    replace: \1\2
  tags:
  - CCE-27464-7
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-2
  - NIST-800-53-IA-2(8)
  - NIST-800-53-IA-2(9)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - use_kerberos_security_all_exports

- name: Add kerberos security when no security is defined for an export
  replace:
    path: /etc/exports
    regexp: ^(/.*\w+.*\(.*)(\)\w*$)
    replace: \1,sec=krb5:krb5i:krb5p\2
  tags:
  - CCE-27464-7
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-2
  - NIST-800-53-IA-2(8)
  - NIST-800-53-IA-2(9)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - use_kerberos_security_all_exports

Complexity:low
Disruption:low
Reboot:false
Strategy:configure

nfs_exports=()
readarray -t nfs_exports < <(grep -E "^/.*[[:space:]]+ .*\(.*\)[[:space:]]*$" /etc/exports | awk '{print $2}')

for nfs_export in "${nfs_exports[@]}"
do
    correct_export=""
    if [ "$(grep -c "sec=" <<<"$nfs_export")" -eq 0 ]; then
        correct_export="$(echo $nfs_export|sed  -e 's/).*$/,sec=krb5\:krb5i\:krb5p)/')"
    else
        correct_export="$(echo $nfs_export|sed  -e 's/sec=[^\,\)]*/sec=krb5\:krb5i\:krb5p/')"
    fi
    sed -i "s|$nfs_export|$correct_export|g" /etc/exports
done
Group   Obsolete Services   Group contains 5 groups and 16 rules
[ref]   This section discusses a number of network-visible services which have historically caused problems for system security, and for which disabling or severely limiting the service has been the best available guidance for some time. As a result of this, many of these services are not installed as part of Red Hat Enterprise Linux 7 by default.

Organizations which are running these services should switch to more secure equivalents as soon as possible. If it remains absolutely necessary to run one of these services for legacy reasons, care should be taken to restrict the service as much as possible, for instance by configuring host firewall software such as firewalld to restrict access to the vulnerable service to only those remote hosts which have a known need to use it.
Group   Xinetd   Group contains 2 rules
[ref]   The xinetd service acts as a dedicated listener for some network services (mostly, obsolete ones) and can be used to provide access controls and perform some logging. It has been largely obsoleted by other features, and it is not installed by default. The older Inetd service is not even available as part of Red Hat Enterprise Linux 7.

Rule   Uninstall xinetd Package   [ref]

The xinetd package can be removed with the following command: 
$ sudo yum erase xinetd
Rationale:
Removing the xinetd package decreases the risk of the xinetd service's accidental (or intentional) activation.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_xinetd_removed
Identifiers:

CCE-27354-0

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000305
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
anssiR62
cis2.2.19
pcidss42.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure xinetd is removed
  package:
    name: xinetd
    state: absent
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27354-0
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_xinetd_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_xinetd

class remove_xinetd {
  package { 'xinetd':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=xinetd

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# CAUTION: This remediation script will remove xinetd
#	   from the system, and may remove any packages
#	   that depend on xinetd. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "xinetd" ; then

    yum remove -y "xinetd"

fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable xinetd Service   [ref]

The xinetd service can be disabled with the following command: 
$ sudo systemctl mask --now xinetd.service
Rationale:
The xinetd service provides a dedicated listener service for some programs, which is no longer necessary for commonly-used network services. Disabling it ensures that these uncommon services are not running, and also prevents attacks against xinetd itself.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_xinetd_disabled
Identifiers:

CCE-27443-1

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
cui3.4.7
disaCCI-000305
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4


[customizations.services]
masked = ["xinetd"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable xinetd Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27443-1
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

- name: Disable xinetd Service - Ensure xinetd.service is Masked
  ansible.builtin.systemd:
    name: xinetd.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("xinetd.service", multiline=True)
  tags:
  - CCE-27443-1
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

- name: Unit Socket Exists - xinetd.socket
  ansible.builtin.command: systemctl -q list-unit-files xinetd.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27443-1
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

- name: Disable xinetd Service - Disable Socket xinetd
  ansible.builtin.systemd:
    name: xinetd.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("xinetd.socket", multiline=True)
  tags:
  - CCE-27443-1
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_xinetd

class disable_xinetd {
  service {'xinetd':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'xinetd.service'
"$SYSTEMCTL_EXEC" disable 'xinetd.service'
"$SYSTEMCTL_EXEC" mask 'xinetd.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files xinetd.socket; then
    "$SYSTEMCTL_EXEC" stop 'xinetd.socket'
    "$SYSTEMCTL_EXEC" mask 'xinetd.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'xinetd.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: xinetd.service
        enabled: false
        mask: true
      - name: xinetd.socket
        enabled: false
        mask: true
Group   NIS   Group contains 3 rules
[ref]   The Network Information Service (NIS), also known as 'Yellow Pages' (YP), and its successor NIS+ have been made obsolete by Kerberos, LDAP, and other modern centralized authentication services. NIS should not be used because it suffers from security problems inherent in its design, such as inadequate protection of important authentication information.

Rule   Remove NIS Client   [ref]

The Network Information Service (NIS), formerly known as Yellow Pages, is a client-server directory service protocol used to distribute system configuration files. The NIS client (ypbind) was used to bind a system to an NIS server and receive the distributed configuration files.
Rationale:
The NIS service is inherently an insecure system that has been vulnerable to DOS attacks, buffer overflows and has poor authentication for querying NIS maps. NIS generally has been replaced by such protocols as Lightweight Directory Access Protocol (LDAP). It is recommended that the service be removed.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_ypbind_removed
Identifiers:

CCE-27396-1

References:
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
anssiR62
cis2.3.3
pcidss42.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure ypbind is removed
  package:
    name: ypbind
    state: absent
  tags:
  - CCE-27396-1
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_ypbind_removed
  - unknown_severity

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_ypbind

class remove_ypbind {
  package { 'ypbind':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=ypbind

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove ypbind
#	   from the system, and may remove any packages
#	   that depend on ypbind. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "ypbind" ; then

    yum remove -y "ypbind"

fi

Rule   Uninstall ypserv Package   [ref]

The ypserv package can be removed with the following command: 
$ sudo yum erase ypserv
Rationale:
The NIS service provides an unencrypted authentication service which does not provide for the confidentiality and integrity of user passwords or the remote session. Removing the ypserv package decreases the risk of the accidental (or intentional) activation of NIS or NIS+ services.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_ypserv_removed
Identifiers:

CCE-27399-5

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000381
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-2.2.2
os-srgSRG-OS-000095-GPOS-00049
stigidRHEL-07-020010
anssiR62
cis2.2.10
pcidss42.2.4
stigrefSV-204443r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure ypserv is removed
  package:
    name: ypserv
    state: absent
  tags:
  - CCE-27399-5
  - DISA-STIG-RHEL-07-020010
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - PCI-DSS-Req-2.2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_ypserv_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_ypserv

class remove_ypserv {
  package { 'ypserv':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=ypserv

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove ypserv
#	   from the system, and may remove any packages
#	   that depend on ypserv. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "ypserv" ; then

    yum remove -y "ypserv"

fi

Rule   Disable ypbind Service   [ref]

The ypbind service, which allows the system to act as a client in a NIS or NIS+ domain, should be disabled. The ypbind service can be disabled with the following command: 
$ sudo systemctl mask --now ypbind.service
Rationale:
Disabling the ypbind service ensures the system is not acting as a client in a NIS or NIS+ domain. This service should be disabled unless in use.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_ypbind_disabled
Identifiers:

CCE-27385-4

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000305
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4


[customizations.services]
masked = ["ypbind"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable ypbind Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27385-4
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypbind_disabled

- name: Disable ypbind Service - Ensure ypbind.service is Masked
  ansible.builtin.systemd:
    name: ypbind.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("ypbind.service", multiline=True)
  tags:
  - CCE-27385-4
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypbind_disabled

- name: Unit Socket Exists - ypbind.socket
  ansible.builtin.command: systemctl -q list-unit-files ypbind.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27385-4
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypbind_disabled

- name: Disable ypbind Service - Disable Socket ypbind
  ansible.builtin.systemd:
    name: ypbind.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("ypbind.socket", multiline=True)
  tags:
  - CCE-27385-4
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypbind_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_ypbind

class disable_ypbind {
  service {'ypbind':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'ypbind.service'
"$SYSTEMCTL_EXEC" disable 'ypbind.service'
"$SYSTEMCTL_EXEC" mask 'ypbind.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files ypbind.socket; then
    "$SYSTEMCTL_EXEC" stop 'ypbind.socket'
    "$SYSTEMCTL_EXEC" mask 'ypbind.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'ypbind.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: ypbind.service
        enabled: false
        mask: true
      - name: ypbind.socket
        enabled: false
        mask: true
Group   Rlogin, Rsh, and Rexec   Group contains 6 rules
[ref]   The Berkeley r-commands are legacy services which allow cleartext remote access and have an insecure trust model.

Rule   Uninstall rsh-server Package   [ref]

The rsh-server package can be removed with the following command: 
$ sudo yum erase rsh-server
Rationale:
The rsh-server service provides unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session and has very weak authentication. If a privileged user were to login using this service, the privileged user password could be compromised. The rsh-server package provides several obsolete and insecure network services. Removing it decreases the risk of those services' accidental (or intentional) activation.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_rsh-server_removed
Identifiers:

CCE-27342-5

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000381
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000095-GPOS-00049
stigidRHEL-07-020000
anssiR62
pcidss42.2.4
stigrefSV-204442r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure rsh-server is removed
  package:
    name: rsh-server
    state: absent
  tags:
  - CCE-27342-5
  - DISA-STIG-RHEL-07-020000
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_rsh-server_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_rsh-server

class remove_rsh-server {
  package { 'rsh-server':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=rsh-server

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove rsh-server
#	   from the system, and may remove any packages
#	   that depend on rsh-server. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "rsh-server" ; then

    yum remove -y "rsh-server"

fi

Rule   Uninstall rsh Package   [ref]

The rsh package contains the client commands for the rsh services
Rationale:
These legacy clients contain numerous security exposures and have been replaced with the more secure SSH package. Even if the server is removed, it is best to ensure the clients are also removed to prevent users from inadvertently attempting to use these commands and therefore exposing their credentials. Note that removing the rsh package removes the clients for rsh,rcp, and rlogin.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_rsh_removed
Identifiers:

CCE-27274-0

References:
cui3.1.13
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
iso27001-2013A.8.2.3, A.13.1.1, A.13.2.1, A.13.2.3, A.14.1.2, A.14.1.3
anssiR62
pcidss42.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure rsh is removed
  package:
    name: rsh
    state: absent
  tags:
  - CCE-27274-0
  - NIST-800-171-3.1.13
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_rsh_removed
  - unknown_severity

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_rsh

class remove_rsh {
  package { 'rsh':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=rsh

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove rsh
#	   from the system, and may remove any packages
#	   that depend on rsh. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "rsh" ; then

    yum remove -y "rsh"

fi

Rule   Disable rexec Service   [ref]

The rexec service, which is available with the rsh-server package and runs as a service through xinetd or separately as a systemd socket, should be disabled. If using xinetd, set disable to yes in /etc/xinetd.d/rexec. The rexec socket can be disabled with the following command: 
$ sudo systemctl mask --now rexec.socket
Rationale:
The rexec service uses unencrypted network communications, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_service_rexec_disabled
Identifiers:

CCE-27408-4

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
cui3.1.13, 3.4.7
disaCCI-000068, CCI-001436
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4


[customizations.services]
masked = ["rexec"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable rexec Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27408-4
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rexec_disabled

- name: Disable rexec Service - Ensure rexec.service is Masked
  ansible.builtin.systemd:
    name: rexec.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("rexec.service", multiline=True)
  tags:
  - CCE-27408-4
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rexec_disabled

- name: Unit Socket Exists - rexec.socket
  ansible.builtin.command: systemctl -q list-unit-files rexec.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27408-4
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rexec_disabled

- name: Disable rexec Service - Disable Socket rexec
  ansible.builtin.systemd:
    name: rexec.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("rexec.socket", multiline=True)
  tags:
  - CCE-27408-4
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rexec_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_rexec

class disable_rexec {
  service {'rexec':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'rexec.service'
"$SYSTEMCTL_EXEC" disable 'rexec.service'
"$SYSTEMCTL_EXEC" mask 'rexec.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files rexec.socket; then
    "$SYSTEMCTL_EXEC" stop 'rexec.socket'
    "$SYSTEMCTL_EXEC" mask 'rexec.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'rexec.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: rexec.service
        enabled: false
        mask: true
      - name: rexec.socket
        enabled: false
        mask: true

Rule   Disable rlogin Service   [ref]

The rlogin service, which is available with the rsh-server package and runs as a service through xinetd or separately as a systemd socket, should be disabled. If using xinetd, set disable to yes in /etc/xinetd.d/rlogin. The rlogin socket can be disabled with the following command: 
$ sudo systemctl mask --now rlogin.socket
Rationale:
The rlogin service uses unencrypted network communications, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_service_rlogin_disabled
Identifiers:

CCE-27336-7

References:
cis-csc1, 11, 12, 14, 15, 16, 3, 5, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
cui3.1.13, 3.4.7
disaCCI-001436
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.18.1.4, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-1, PR.AC-3, PR.AC-6, PR.AC-7, PR.IP-1, PR.PT-3, PR.PT-4


[customizations.services]
masked = ["rlogin"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable rlogin Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27336-7
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rlogin_disabled

- name: Disable rlogin Service - Ensure rlogin.service is Masked
  ansible.builtin.systemd:
    name: rlogin.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("rlogin.service", multiline=True)
  tags:
  - CCE-27336-7
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rlogin_disabled

- name: Unit Socket Exists - rlogin.socket
  ansible.builtin.command: systemctl -q list-unit-files rlogin.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27336-7
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rlogin_disabled

- name: Disable rlogin Service - Disable Socket rlogin
  ansible.builtin.systemd:
    name: rlogin.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("rlogin.socket", multiline=True)
  tags:
  - CCE-27336-7
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rlogin_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_rlogin

class disable_rlogin {
  service {'rlogin':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'rlogin.service'
"$SYSTEMCTL_EXEC" disable 'rlogin.service'
"$SYSTEMCTL_EXEC" mask 'rlogin.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files rlogin.socket; then
    "$SYSTEMCTL_EXEC" stop 'rlogin.socket'
    "$SYSTEMCTL_EXEC" mask 'rlogin.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'rlogin.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: rlogin.service
        enabled: false
        mask: true
      - name: rlogin.socket
        enabled: false
        mask: true

Rule   Disable rsh Service   [ref]

The rsh service, which is available with the rsh-server package and runs as a service through xinetd or separately as a systemd socket, should be disabled. If using xinetd, set disable to yes in /etc/xinetd.d/rsh. The rsh socket can be disabled with the following command: 
$ sudo systemctl mask --now rsh.socket
Rationale:
The rsh service uses unencrypted network communications, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_service_rsh_disabled
Identifiers:

CCE-27337-5

References:
cis-csc1, 11, 12, 14, 15, 16, 3, 5, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
cui3.1.13, 3.4.7
disaCCI-000068, CCI-001436
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.18.1.4, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-1, PR.AC-3, PR.AC-6, PR.AC-7, PR.IP-1, PR.PT-3, PR.PT-4


[customizations.services]
masked = ["rsh"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable rsh Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27337-5
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rsh_disabled

- name: Disable rsh Service - Ensure rsh.service is Masked
  ansible.builtin.systemd:
    name: rsh.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("rsh.service", multiline=True)
  tags:
  - CCE-27337-5
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rsh_disabled

- name: Unit Socket Exists - rsh.socket
  ansible.builtin.command: systemctl -q list-unit-files rsh.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27337-5
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rsh_disabled

- name: Disable rsh Service - Disable Socket rsh
  ansible.builtin.systemd:
    name: rsh.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("rsh.socket", multiline=True)
  tags:
  - CCE-27337-5
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_rsh_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_rsh

class disable_rsh {
  service {'rsh':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'rsh.service'
"$SYSTEMCTL_EXEC" disable 'rsh.service'
"$SYSTEMCTL_EXEC" mask 'rsh.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files rsh.socket; then
    "$SYSTEMCTL_EXEC" stop 'rsh.socket'
    "$SYSTEMCTL_EXEC" mask 'rsh.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'rsh.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: rsh.service
        enabled: false
        mask: true
      - name: rsh.socket
        enabled: false
        mask: true

Rule   Remove Rsh Trust Files   [ref]

The files /etc/hosts.equiv and ~/.rhosts (in each user's home directory) list remote hosts and users that are trusted by the local system when using the rshd daemon. To remove these files, run the following command to delete them from any location: 
$ sudo rm /etc/hosts.equiv
$ rm ~/.rhosts
Rationale:
This action is only meaningful if .rhosts support is permitted through PAM. Trust files are convenient, but when used in conjunction with the R-services, they can allow unauthenticated access to a system.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_no_rsh_trust_files
Identifiers:

CCE-27406-8

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-001436
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
cis6.2.11

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27406-8
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - no_rsh_trust_files
  - restrict_strategy

- name: Detect .rhosts files in users home directories
  find:
    paths:
    - /root
    - /home
    recurse: true
    patterns: .rhosts
    hidden: true
    file_type: file
  check_mode: false
  register: rhosts_locations
  when: '"rsh-server" in ansible_facts.packages'
  tags:
  - CCE-27406-8
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - no_rsh_trust_files
  - restrict_strategy

- name: Remove .rhosts files
  file:
    path: '{{ item }}'
    state: absent
  with_items: '{{ rhosts_locations.files | map(attribute=''path'') | list }}'
  when:
  - '"rsh-server" in ansible_facts.packages'
  - rhosts_locations is success
  tags:
  - CCE-27406-8
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - no_rsh_trust_files
  - restrict_strategy

- name: Remove /etc/hosts.equiv file
  file:
    path: /etc/hosts.equiv
    state: absent
  when: '"rsh-server" in ansible_facts.packages'
  tags:
  - CCE-27406-8
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - no_rsh_trust_files
  - restrict_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q rsh-server; then

find /root -xdev -type f -name ".rhosts" -exec rm -f {} \;
find /home -maxdepth 2 -xdev -type f -name ".rhosts" -exec rm -f {} \;
rm -f /etc/hosts.equiv

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Chat/Messaging Services   Group contains 2 rules
[ref]   The talk software makes it possible for users to send and receive messages across systems through a terminal session.

Rule   Uninstall talk-server Package   [ref]

The talk-server package can be removed with the following command: 
 $ sudo yum erase talk-server
Rationale:
The talk software presents a security risk as it uses unencrypted protocols for communications. Removing the talk-server package decreases the risk of the accidental (or intentional) activation of talk services.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_talk-server_removed
Identifiers:

CCE-27210-4

References:
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
anssiR62
pcidss42.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure talk-server is removed
  package:
    name: talk-server
    state: absent
  tags:
  - CCE-27210-4
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_talk-server_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_talk-server

class remove_talk-server {
  package { 'talk-server':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=talk-server

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove talk-server
#	   from the system, and may remove any packages
#	   that depend on talk-server. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "talk-server" ; then

    yum remove -y "talk-server"

fi

Rule   Uninstall talk Package   [ref]

The talk package contains the client program for the Internet talk protocol, which allows the user to chat with other users on different systems. Talk is a communication program which copies lines from one terminal to the terminal of another user. The talk package can be removed with the following command: 
$ sudo yum erase talk
Rationale:
The talk software presents a security risk as it uses unencrypted protocols for communications. Removing the talk package decreases the risk of the accidental (or intentional) activation of talk client program.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_talk_removed
Identifiers:

CCE-27432-4

References:
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
anssiR62
pcidss42.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure talk is removed
  package:
    name: talk
    state: absent
  tags:
  - CCE-27432-4
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_talk_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_talk

class remove_talk {
  package { 'talk':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=talk

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove talk
#	   from the system, and may remove any packages
#	   that depend on talk. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "talk" ; then

    yum remove -y "talk"

fi
Group   Telnet   Group contains 3 rules
[ref]   The telnet protocol does not provide confidentiality or integrity for information transmitted on the network. This includes authentication information such as passwords. Organizations which use telnet should be actively working to migrate to a more secure protocol.

Rule   Uninstall telnet-server Package   [ref]

The telnet-server package can be removed with the following command: 
$ sudo yum erase telnet-server
Rationale:
It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities are often overlooked and therefore may remain unsecure. They increase the risk to the platform by providing additional attack vectors.
The telnet service provides an unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to login using this service, the privileged user password could be compromised.
Removing the telnet-server package decreases the risk of the telnet service's accidental (or intentional) activation.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_telnet-server_removed
Identifiers:

CCE-27165-0

References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000381
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-2.2.2
os-srgSRG-OS-000095-GPOS-00049
stigidRHEL-07-021710
anssiR62
cis2.2.15
pcidss42.2.4
stigrefSV-204502r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure telnet-server is removed
  package:
    name: telnet-server
    state: absent
  tags:
  - CCE-27165-0
  - DISA-STIG-RHEL-07-021710
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-2.2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_telnet-server_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_telnet-server

class remove_telnet-server {
  package { 'telnet-server':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=telnet-server

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove telnet-server
#	   from the system, and may remove any packages
#	   that depend on telnet-server. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "telnet-server" ; then

    yum remove -y "telnet-server"

fi

Rule   Remove telnet Clients   [ref]

The telnet client allows users to start connections to other systems via the telnet protocol.
Rationale:
The telnet protocol is insecure and unencrypted. The use of an unencrypted transmission medium could allow an unauthorized user to steal credentials. The ssh package provides an encrypted session and stronger security and is included in Red Hat Enterprise Linux 7.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_telnet_removed
Identifiers:

CCE-27305-2

References:
cui3.1.13
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
iso27001-2013A.8.2.3, A.13.1.1, A.13.2.1, A.13.2.3, A.14.1.2, A.14.1.3
anssiR62
cis2.3.4
pcidss42.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure telnet is removed
  package:
    name: telnet
    state: absent
  tags:
  - CCE-27305-2
  - NIST-800-171-3.1.13
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_telnet_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_telnet

class remove_telnet {
  package { 'telnet':
    ensure => 'purged',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

package --remove=telnet

Complexity:low
Disruption:low
Reboot:false
Strategy:disable

# CAUTION: This remediation script will remove telnet
#	   from the system, and may remove any packages
#	   that depend on telnet. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

if rpm -q --quiet "telnet" ; then

    yum remove -y "telnet"

fi

Rule   Disable telnet Service   [ref]

Make sure that the activation of the telnet service on system boot is disabled. The telnet socket can be disabled with the following command: 
$ sudo systemctl mask --now telnet.socket
Warning:  If the system relies on xinetd to manage telnet sessions, ensure the telnet service is disabled by the following line: disable = yes. Note that the xinetd file for telnet is not created automatically, therefore it might have different names.
Rationale:
The telnet protocol uses unencrypted network communication, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network. The telnet protocol is also subject to man-in-the-middle attacks.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_service_telnet_disabled
Identifiers:

CCE-27401-9

References:
cis-csc1, 11, 12, 14, 15, 16, 3, 5, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
cui3.1.13, 3.4.7
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.18.1.4, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-1, PR.AC-3, PR.AC-6, PR.AC-7, PR.IP-1, PR.PT-3, PR.PT-4


[customizations.services]
masked = ["telnet"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27401-9
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_telnet_disabled

- name: Disable telnet Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman",
    "container"] and "telnet-server" in ansible_facts.packages )
  tags:
  - CCE-27401-9
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_telnet_disabled

- name: Disable telnet Service - Ensure telnet.service is Masked
  ansible.builtin.systemd:
    name: telnet.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    and "telnet-server" in ansible_facts.packages )
  - service_exists.stdout_lines is search("telnet.service", multiline=True)
  tags:
  - CCE-27401-9
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_telnet_disabled

- name: Unit Socket Exists - telnet.socket
  ansible.builtin.command: systemctl -q list-unit-files telnet.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman",
    "container"] and "telnet-server" in ansible_facts.packages )
  tags:
  - CCE-27401-9
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_telnet_disabled

- name: Disable telnet Service - Disable Socket telnet
  ansible.builtin.systemd:
    name: telnet.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
    and "telnet-server" in ansible_facts.packages )
  - socket_file_exists.stdout_lines is search("telnet.socket", multiline=True)
  tags:
  - CCE-27401-9
  - NIST-800-171-3.1.13
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_telnet_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_telnet

class disable_telnet {
  service {'telnet':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q telnet-server ); then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'telnet.service'
"$SYSTEMCTL_EXEC" disable 'telnet.service'
"$SYSTEMCTL_EXEC" mask 'telnet.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files telnet.socket; then
    "$SYSTEMCTL_EXEC" stop 'telnet.socket'
    "$SYSTEMCTL_EXEC" mask 'telnet.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'telnet.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: telnet.service
        enabled: false
        mask: true
      - name: telnet.socket
        enabled: false
        mask: true
Group   Network Routing   Group contains 1 group and 1 rule
[ref]   A router is a very desirable target for a potential adversary because they fulfill a variety of infrastructure networking roles such as access to network segments, gateways to other networks, filtering, etc. Therefore, if one is required, the system acting as a router should be dedicated to that purpose alone and be stored in a physically secure location. The system's default routing software is Quagga, and provided in an RPM package of the same name.
Group   Disable Quagga if Possible   Group contains 1 rule
[ref]   If Quagga was installed and activated, but the system does not need to act as a router, then it should be disabled and removed.

Rule   Disable Quagga Service   [ref]

The zebra service can be disabled with the following command: 
$ sudo systemctl mask --now zebra.service
Rationale:
Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If routing daemons are used when not required, system network information may be unnecessarily transmitted across the network.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_zebra_disabled
Identifiers:

CCE-27191-6

References:
cis-csc12, 15, 8
cobit5APO13.01, DSS05.02
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-2013SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.13.1.1, A.13.2.1, A.14.1.3
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.PT-4
os-srgSRG-OS-000480-GPOS-00227


[customizations.services]
masked = ["zebra"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Disable Quagga Service - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27191-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_zebra_disabled

- name: Disable Quagga Service - Ensure zebra.service is Masked
  ansible.builtin.systemd:
    name: zebra.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - service_exists.stdout_lines is search("zebra.service", multiline=True)
  tags:
  - CCE-27191-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_zebra_disabled

- name: Unit Socket Exists - zebra.socket
  ansible.builtin.command: systemctl -q list-unit-files zebra.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27191-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_zebra_disabled

- name: Disable Quagga Service - Disable Socket zebra
  ansible.builtin.systemd:
    name: zebra.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - socket_file_exists.stdout_lines is search("zebra.socket", multiline=True)
  tags:
  - CCE-27191-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_zebra_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_zebra

class disable_zebra {
  service {'zebra':
    enable => false,
    ensure => 'stopped',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'zebra.service'
"$SYSTEMCTL_EXEC" disable 'zebra.service'
"$SYSTEMCTL_EXEC" mask 'zebra.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files zebra.socket; then
    "$SYSTEMCTL_EXEC" stop 'zebra.socket'
    "$SYSTEMCTL_EXEC" mask 'zebra.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'zebra.service' || true

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: zebra.service
        enabled: false
        mask: true
      - name: zebra.socket
        enabled: false
        mask: true
Group   SSH Server   Group contains 1 group and 14 rules
[ref]   The SSH protocol is recommended for remote login and remote file transfer. SSH provides confidentiality and integrity for data exchanged between two systems, as well as server authentication, through the use of public key cryptography. The implementation included with the system is called OpenSSH, and more detailed documentation is available from its website, https://www.openssh.com. Its server program is called sshd and provided by the RPM package openssh-server.
Group   Configure OpenSSH Server if Necessary   Group contains 14 rules
[ref]   If the system needs to act as an SSH server, then certain changes should be made to the OpenSSH daemon configuration file /etc/ssh/sshd_config. The following recommendations can be applied to this file. See the sshd_config(5) man page for more detailed information.

Rule   Set SSH Client Alive Count Max to zero   [ref]

The SSH server sends at most ClientAliveCountMax messages during a SSH session and waits for a response from the SSH client. The option ClientAliveInterval configures timeout after each ClientAliveCountMax message. If the SSH server does not receive a response from the client, then the connection is considered unresponsive and terminated. To ensure the SSH timeout occurs precisely when the ClientAliveInterval is set, set the ClientAliveCountMax to value of 0 in /etc/ssh/sshd_config:
Rationale:
This ensures a user login will be terminated as soon as the ClientAliveInterval is reached.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_keepalive_0
Identifiers:

CCE-83399-6

References:
cis-csc1, 12, 13, 14, 15, 16, 18, 3, 5, 7, 8
cjis5.5.6
cobit5APO13.01, BAI03.01, BAI03.02, BAI03.03, DSS01.03, DSS03.05, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.1.11
disaCCI-000879, CCI-001133, CCI-002361
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.3, A.14.1.1, A.14.2.1, A.14.2.5, A.18.1.4, A.6.1.2, A.6.1.5, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-004-6 R2.2.3, CIP-007-3 R5.1, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3
nistAC-2(5), AC-12, AC-17(a), SC-10, CM-6(a)
nist-csfDE.CM-1, DE.CM-3, PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.IP-2
pcidssReq-8.1.8
os-srgSRG-OS-000126-GPOS-00066, SRG-OS-000163-GPOS-00072, SRG-OS-000279-GPOS-00109
stigidRHEL-07-040340
stigrefSV-204589r917836_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Set SSH Client Alive Count Max to zero
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*ClientAliveCountMax\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*ClientAliveCountMax\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*ClientAliveCountMax\s+
      line: ClientAliveCountMax 0
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-83399-6
  - CJIS-5.5.6
  - DISA-STIG-RHEL-07-040340
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSS-Req-8.1.8
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_keepalive_0

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*ClientAliveCountMax\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "ClientAliveCountMax 0" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable Host-Based Authentication   [ref]

SSH's cryptographic host-based authentication is more secure than .rhosts authentication. However, it is not recommended that hosts unilaterally trust one another, even within an organization.
The default SSH configuration disables host-based authentication. The appropriate configuration is used if no value is set for HostbasedAuthentication.
To explicitly disable host-based authentication, add or correct the following line in /etc/ssh/sshd_config: 
HostbasedAuthentication no
Rationale:
SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_disable_host_auth
Identifiers:

CCE-27413-4

References:
cis-csc11, 12, 14, 15, 16, 18, 3, 5, 9
cjis5.5.6
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06
cui3.1.12
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3
nistAC-3, AC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.IP-1, PR.PT-3
osppFIA_UAU.1
os-srgSRG-OS-000480-GPOS-00229
stigidRHEL-07-010470
cis4.2.10
pcidss48.3.1
stigrefSV-204435r877377_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Disable Host-Based Authentication
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*HostbasedAuthentication\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*HostbasedAuthentication\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*HostbasedAuthentication\s+
      line: HostbasedAuthentication no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27413-4
  - CJIS-5.5.6
  - DISA-STIG-RHEL-07-010470
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSSv4-8.3.1
  - disable_host_auth
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*HostbasedAuthentication\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "HostbasedAuthentication no" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,%23%09%24OpenBSD%3A%20sshd_config%2Cv%201.103%202018%2F04%2F09%2020%3A41%3A22%20tj%20Exp%20%24%0A%0A%23%20This%20is%20the%20sshd%20server%20system-wide%20configuration%20file.%20%20See%0A%23%20sshd_config%285%29%20for%20more%20information.%0A%0A%23%20This%20sshd%20was%20compiled%20with%20PATH%3D%2Fusr%2Flocal%2Fbin%3A%2Fusr%2Fbin%3A%2Fusr%2Flocal%2Fsbin%3A%2Fusr%2Fsbin%0A%0A%23%20The%20strategy%20used%20for%20options%20in%20the%20default%20sshd_config%20shipped%20with%0A%23%20OpenSSH%20is%20to%20specify%20options%20with%20their%20default%20value%20where%0A%23%20possible%2C%20but%20leave%20them%20commented.%20%20Uncommented%20options%20override%20the%0A%23%20default%20value.%0A%0A%23%20If%20you%20want%20to%20change%20the%20port%20on%20a%20SELinux%20system%2C%20you%20have%20to%20tell%0A%23%20SELinux%20about%20this%20change.%0A%23%20semanage%20port%20-a%20-t%20ssh_port_t%20-p%20tcp%20%23PORTNUMBER%0A%23%0A%23Port%2022%0A%23AddressFamily%20any%0A%23ListenAddress%200.0.0.0%0A%23ListenAddress%20%3A%3A%0A%0AHostKey%20%2Fetc%2Fssh%2Fssh_host_rsa_key%0AHostKey%20%2Fetc%2Fssh%2Fssh_host_ecdsa_key%0AHostKey%20%2Fetc%2Fssh%2Fssh_host_ed25519_key%0A%0A%23%20Ciphers%20and%20keying%0ARekeyLimit%20512M%201h%0A%0A%23%20System-wide%20Crypto%20policy%3A%0A%23%20This%20system%20is%20following%20system-wide%20crypto%20policy.%20The%20changes%20to%0A%23%20Ciphers%2C%20MACs%2C%20KexAlgoritms%20and%20GSSAPIKexAlgorithsm%20will%20not%20have%20any%0A%23%20effect%20here.%20They%20will%20be%20overridden%20by%20command-line%20options%20passed%20on%0A%23%20the%20server%20start%20up.%0A%23%20To%20opt%20out%2C%20uncomment%20a%20line%20with%20redefinition%20of%20%20CRYPTO_POLICY%3D%0A%23%20variable%20in%20%20%2Fetc%2Fsysconfig%2Fsshd%20%20to%20overwrite%20the%20policy.%0A%23%20For%20more%20information%2C%20see%20manual%20page%20for%20update-crypto-policies%288%29.%0A%0A%23%20Logging%0A%23SyslogFacility%20AUTH%0ASyslogFacility%20AUTHPRIV%0A%23LogLevel%20INFO%0A%0A%23%20Authentication%3A%0A%0A%23LoginGraceTime%202m%0APermitRootLogin%20no%0AStrictModes%20yes%0A%23MaxAuthTries%206%0A%23MaxSessions%2010%0A%0APubkeyAuthentication%20yes%0A%0A%23%20The%20default%20is%20to%20check%20both%20.ssh%2Fauthorized_keys%20and%20.ssh%2Fauthorized_keys2%0A%23%20but%20this%20is%20overridden%20so%20installations%20will%20only%20check%20.ssh%2Fauthorized_keys%0AAuthorizedKeysFile%09.ssh%2Fauthorized_keys%0A%0A%23AuthorizedPrincipalsFile%20none%0A%0A%23AuthorizedKeysCommand%20none%0A%23AuthorizedKeysCommandUser%20nobody%0A%0A%23%20For%20this%20to%20work%20you%20will%20also%20need%20host%20keys%20in%20%2Fetc%2Fssh%2Fssh_known_hosts%0AHostbasedAuthentication%20no%0A%23%20Change%20to%20yes%20if%20you%20don%27t%20trust%20~%2F.ssh%2Fknown_hosts%20for%0A%23%20HostbasedAuthentication%0AIgnoreUserKnownHosts%20yes%0A%23%20Don%27t%20read%20the%20user%27s%20~%2F.rhosts%20and%20~%2F.shosts%20files%0AIgnoreRhosts%20yes%0A%0A%23%20To%20disable%20tunneled%20clear%20text%20passwords%2C%20change%20to%20no%20here%21%0A%23PasswordAuthentication%20yes%0APermitEmptyPasswords%20no%0APasswordAuthentication%20no%0A%0A%23%20Change%20to%20no%20to%20disable%20s%2Fkey%20passwords%0A%23ChallengeResponseAuthentication%20yes%0AChallengeResponseAuthentication%20no%0A%0A%23%20Kerberos%20options%0AKerberosAuthentication%20no%0A%23KerberosOrLocalPasswd%20yes%0A%23KerberosTicketCleanup%20yes%0A%23KerberosGetAFSToken%20no%0A%23KerberosUseKuserok%20yes%0A%0A%23%20GSSAPI%20options%0AGSSAPIAuthentication%20no%0AGSSAPICleanupCredentials%20no%0A%23GSSAPIStrictAcceptorCheck%20yes%0A%23GSSAPIKeyExchange%20no%0A%23GSSAPIEnablek5users%20no%0A%0A%23%20Set%20this%20to%20%27yes%27%20to%20enable%20PAM%20authentication%2C%20account%20processing%2C%0A%23%20and%20session%20processing.%20If%20this%20is%20enabled%2C%20PAM%20authentication%20will%0A%23%20be%20allowed%20through%20the%20ChallengeResponseAuthentication%20and%0A%23%20PasswordAuthentication.%20%20Depending%20on%20your%20PAM%20configuration%2C%0A%23%20PAM%20authentication%20via%20ChallengeResponseAuthentication%20may%20bypass%0A%23%20the%20setting%20of%20%22PermitRootLogin%20without-password%22.%0A%23%20If%20you%20just%20want%20the%20PAM%20account%20and%20session%20checks%20to%20run%20without%0A%23%20PAM%20authentication%2C%20then%20enable%20this%20but%20set%20PasswordAuthentication%0A%23%20and%20ChallengeResponseAuthentication%20to%20%27no%27.%0A%23%20WARNING%3A%20%27UsePAM%20no%27%20is%20not%20supported%20in%20Fedora%20and%20may%20cause%20several%0A%23%20problems.%0AUsePAM%20yes%0A%0A%23AllowAgentForwarding%20yes%0A%23AllowTcpForwarding%20yes%0A%23GatewayPorts%20no%0AX11Forwarding%20yes%0A%23X11DisplayOffset%2010%0A%23X11UseLocalhost%20yes%0A%23PermitTTY%20yes%0A%0A%23%20It%20is%20recommended%20to%20use%20pam_motd%20in%20%2Fetc%2Fpam.d%2Fsshd%20instead%20of%20PrintMotd%2C%0A%23%20as%20it%20is%20more%20configurable%20and%20versatile%20than%20the%20built-in%20version.%0APrintMotd%20no%0A%0APrintLastLog%20yes%0A%23TCPKeepAlive%20yes%0APermitUserEnvironment%20no%0ACompression%20no%0AClientAliveInterval%20600%0AClientAliveCountMax%200%0A%23UseDNS%20no%0A%23PidFile%20%2Fvar%2Frun%2Fsshd.pid%0A%23MaxStartups%2010%3A30%3A100%0A%23PermitTunnel%20no%0A%23ChrootDirectory%20none%0A%23VersionAddendum%20none%0A%0A%23%20no%20default%20banner%20path%0ABanner%20%2Fetc%2Fissue%0A%0A%23%20Accept%20locale-related%20environment%20variables%0AAcceptEnv%20LANG%20LC_CTYPE%20LC_NUMERIC%20LC_TIME%20LC_COLLATE%20LC_MONETARY%20LC_MESSAGES%0AAcceptEnv%20LC_PAPER%20LC_NAME%20LC_ADDRESS%20LC_TELEPHONE%20LC_MEASUREMENT%0AAcceptEnv%20LC_IDENTIFICATION%20LC_ALL%20LANGUAGE%0AAcceptEnv%20XMODIFIERS%0A%0A%23%20override%20default%20of%20no%20subsystems%0ASubsystem%09sftp%09%2Fusr%2Flibexec%2Fopenssh%2Fsftp-server%0A%0A%23%20Example%20of%20overriding%20settings%20on%20a%20per-user%20basis%0A%23Match%20User%20anoncvs%0A%23%09X11Forwarding%20no%0A%23%09AllowTcpForwarding%20no%0A%23%09PermitTTY%20no%0A%23%09ForceCommand%20cvs%20server%0A%0AUsePrivilegeSeparation%20sandbox
        mode: 0600
        path: /etc/ssh/sshd_config
        overwrite: true

Rule   Allow Only SSH Protocol 2   [ref]

Only SSH protocol version 2 connections should be permitted. The default setting in /etc/ssh/sshd_config is correct, and can be verified by ensuring that the following line appears: 
Protocol 2
Warning:  As of openssh-server version 7.4 and above, the only protocol supported is version 2, and line 
Protocol 2
in /etc/ssh/sshd_config is not necessary.
Rationale:
SSH protocol version 1 is an insecure implementation of the SSH protocol and has many well-known vulnerability exploits. Exploits of the SSH daemon could provide immediate root access to the system.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_sshd_allow_only_protocol2
Identifiers:

CCE-27320-1

References:
cis-csc1, 12, 15, 16, 5, 8
cjis5.5.6
cobit5APO13.01, DSS01.04, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.1.13, 3.5.4
disaCCI-000197, CCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.6, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
ism0487, 1449, 1506
iso27001-2013A.11.2.6, A.13.1.1, A.13.2.1, A.14.1.3, A.18.1.4, A.6.2.1, A.6.2.2, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3
nerc-cipCIP-003-8 R4.2, CIP-007-3 R5.1, CIP-007-3 R7.1
nistCM-6(a), AC-17(a), AC-17(2), IA-5(1)(c), SC-13, MA-4(6)
nist-csfPR.AC-1, PR.AC-3, PR.AC-6, PR.AC-7, PR.PT-4
os-srgSRG-OS-000074-GPOS-00042, SRG-OS-000480-GPOS-00227
stigidRHEL-07-040390
stigrefSV-204594r877396_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Allow Only SSH Protocol 2
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Protocol\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Protocol\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Protocol\s+
      line: Protocol 2
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27320-1
  - CJIS-5.5.6
  - DISA-STIG-RHEL-07-040390
  - NIST-800-171-3.1.13
  - NIST-800-171-3.5.4
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-MA-4(6)
  - NIST-800-53-SC-13
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy
  - sshd_allow_only_protocol2


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^Protocol")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "2"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^Protocol\\>" "/etc/ssh/sshd_config"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^Protocol\\>.*/$escaped_formatted_output/gi" "/etc/ssh/sshd_config"
else
    if [[ -s "/etc/ssh/sshd_config" ]] && [[ -n "$(tail -c 1 -- "/etc/ssh/sshd_config" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/ssh/sshd_config"
    fi
    cce="CCE-27320-1"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/ssh/sshd_config" >> "/etc/ssh/sshd_config"
    printf '%s\n' "$formatted_output" >> "/etc/ssh/sshd_config"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable Compression Or Set Compression to delayed   [ref]

Compression is useful for slow network connections over long distances but can cause performance issues on local LANs. If use of compression is required, it should be enabled only after a user has authenticated; otherwise, it should be disabled. To disable compression or delay compression until after a user has successfully authenticated, add or correct the following line in the /etc/ssh/sshd_config file: 
Compression no
Rationale:
If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_disable_compression
Identifiers:

CCE-80224-9

References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
cui3.1.12
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 7.6
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4
nistAC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1
os-srgSRG-OS-000480-GPOS-00227
stigidRHEL-07-040470
stigrefSV-204602r880758_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value var_sshd_disable_compression # promote to variable
  set_fact:
    var_sshd_disable_compression: !!str no
  tags:
    - always

- name: Disable Compression Or Set Compression to delayed
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Compression\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Compression\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Compression\s+
      line: Compression {{ var_sshd_disable_compression }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_distribution == 'RedHat' and ansible_distribution_version is version('7.4',
    '<')
  tags:
  - CCE-80224-9
  - DISA-STIG-RHEL-07-040470
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_compression


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { grep -qP "^ID=[\"']?rhel[\"']?$" "/etc/os-release" && { real="$(grep -P "^VERSION_ID=[\"']?[\w.]+[\"']?$" /etc/os-release | sed "s/^VERSION_ID=[\"']\?\([^\"']\+\)[\"']\?$/\1/")"; expected="7.4"; [[ "$real" != "$expected" ]] && printf "%s\n%s" "$real" "$expected" | sort -VC; }; }; then

var_sshd_disable_compression='no'



if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*Compression\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "Compression $var_sshd_disable_compression" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable SSH Access via Empty Passwords   [ref]

Disallow SSH login with empty passwords. The default SSH configuration disables logins with empty passwords. The appropriate configuration is used if no value is set for PermitEmptyPasswords.
To explicitly disallow SSH login from accounts with empty passwords, add or correct the following line in /etc/ssh/sshd_config: 
PermitEmptyPasswords no
Any accounts with empty passwords should be disabled immediately, and PAM configuration should prevent users from being able to assign themselves empty passwords.
Rationale:
Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_sshd_disable_empty_passwords
Identifiers:

CCE-27471-2

References:
cis-csc11, 12, 13, 14, 15, 16, 18, 3, 5, 9
cjis5.5.6
cobit5APO01.06, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06
cui3.1.1, 3.1.5
disaCCI-000366, CCI-000766
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 5.2, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistAC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.DS-5, PR.IP-1, PR.PT-3
osppFIA_UAU.1
pcidssReq-2.2.4
os-srgSRG-OS-000106-GPOS-00053, SRG-OS-000480-GPOS-00229, SRG-OS-000480-GPOS-00227
stigidRHEL-07-010300
cis4.2.19
pcidss42.2.6
stigrefSV-204425r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Disable SSH Access via Empty Passwords
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*PermitEmptyPasswords\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*PermitEmptyPasswords\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*PermitEmptyPasswords\s+
      line: PermitEmptyPasswords no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27471-2
  - CJIS-5.5.6
  - DISA-STIG-RHEL-07-010300
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2.6
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_empty_passwords

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*PermitEmptyPasswords\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "PermitEmptyPasswords no" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable GSSAPI Authentication   [ref]

Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like GSSAPI.
The default SSH configuration disallows authentications based on GSSAPI. The appropriate configuration is used if no value is set for GSSAPIAuthentication.
To explicitly disable GSSAPI authentication, add or correct the following line in /etc/ssh/sshd_config: 
GSSAPIAuthentication no
Rationale:
GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing the attack surface of the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_disable_gssapi_auth
Identifiers:

CCE-80220-7

References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
cui3.1.12
disaCCI-000318, CCI-000368, CCI-001812, CCI-001813, CCI-001814, CCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 7.6
ism0418, 1055, 1402
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4
nistCM-7(a), CM-7(b), CM-6(a), AC-17(a)
nist-csfPR.IP-1
osppFTP_ITC_EXT.1, FCS_SSH_EXT.1.2
os-srgSRG-OS-000364-GPOS-00151, SRG-OS-000480-GPOS-00227
stigidRHEL-07-040430
cis4.2.9
stigrefSV-204598r853993_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Disable GSSAPI Authentication
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*GSSAPIAuthentication\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*GSSAPIAuthentication\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*GSSAPIAuthentication\s+
      line: GSSAPIAuthentication no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80220-7
  - DISA-STIG-RHEL-07-040430
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_gssapi_auth

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*GSSAPIAuthentication\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "GSSAPIAuthentication no" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable Kerberos Authentication   [ref]

Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like Kerberos.
The default SSH configuration disallows authentication validation through Kerberos. The appropriate configuration is used if no value is set for KerberosAuthentication.
To explicitly disable Kerberos authentication, add or correct the following line in /etc/ssh/sshd_config: 
KerberosAuthentication no
Rationale:
Kerberos authentication for SSH is often implemented using GSSAPI. If Kerberos is enabled through SSH, the SSH daemon provides a means of access to the system's Kerberos implementation. Configuring these settings for the SSH daemon provides additional assurance that remote logon via SSH will not use unused methods of authentication, even in the event of misconfiguration elsewhere.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_disable_kerb_auth
Identifiers:

CCE-80221-5

References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
cui3.1.12
disaCCI-000318, CCI-000368, CCI-001812, CCI-001813, CCI-001814, CCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 7.6
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4
nistAC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1
osppFTP_ITC_EXT.1, FCS_SSH_EXT.1.2
os-srgSRG-OS-000364-GPOS-00151, SRG-OS-000480-GPOS-00227
stigidRHEL-07-040440
stigrefSV-204599r853994_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Disable Kerberos Authentication
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*KerberosAuthentication\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*KerberosAuthentication\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*KerberosAuthentication\s+
      line: KerberosAuthentication no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80221-5
  - DISA-STIG-RHEL-07-040440
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_kerb_auth

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*KerberosAuthentication\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "KerberosAuthentication no" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable SSH Support for Rhosts RSA Authentication   [ref]

SSH can allow authentication through the obsolete rsh command through the use of the authenticating user's SSH keys. This should be disabled.

To ensure this behavior is disabled, add or correct the following line in /etc/ssh/sshd_config: 
RhostsRSAAuthentication no
Warning:  As of openssh-server version 7.4 and above, the RhostsRSAAuthentication option has been deprecated, and the line 
RhostsRSAAuthentication no
in /etc/ssh/sshd_config is not necessary.
Rationale:
Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_disable_rhosts_rsa
Identifiers:

CCE-80373-4

References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
cui3.1.12
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 7.6
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4
nistAC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1
osppFIA_UAU.1
os-srgSRG-OS-000480-GPOS-00227
stigidRHEL-07-040330
stigrefSV-204588r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Disable SSH Support for Rhosts RSA Authentication
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*RhostsRSAAuthentication\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*RhostsRSAAuthentication\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*RhostsRSAAuthentication\s+
      line: RhostsRSAAuthentication no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80373-4
  - DISA-STIG-RHEL-07-040330
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_rhosts_rsa


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^RhostsRSAAuthentication")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "no"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^RhostsRSAAuthentication\\>" "/etc/ssh/sshd_config"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^RhostsRSAAuthentication\\>.*/$escaped_formatted_output/gi" "/etc/ssh/sshd_config"
else
    if [[ -s "/etc/ssh/sshd_config" ]] && [[ -n "$(tail -c 1 -- "/etc/ssh/sshd_config" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/ssh/sshd_config"
    fi
    cce="CCE-80373-4"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/ssh/sshd_config" >> "/etc/ssh/sshd_config"
    printf '%s\n' "$formatted_output" >> "/etc/ssh/sshd_config"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Do Not Allow SSH Environment Options   [ref]

Ensure that users are not able to override environment variables of the SSH daemon.
The default SSH configuration disables environment processing. The appropriate configuration is used if no value is set for PermitUserEnvironment.
To explicitly disable Environment options, add or correct the following /etc/ssh/sshd_config: 
PermitUserEnvironment no
Rationale:
SSH environment options potentially allow users to bypass access restriction in some configurations.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_do_not_permit_user_env
Identifiers:

CCE-27363-1

References:
cis-csc11, 3, 9
cjis5.5.6
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
cui3.1.12
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 7.6
iso27001-2013A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4
nistAC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1
pcidssReq-2.2.4
os-srgSRG-OS-000480-GPOS-00229
stigidRHEL-07-010460
cis4.2.21
pcidss42.2.6
stigrefSV-204434r877377_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Do Not Allow SSH Environment Options
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*PermitUserEnvironment\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*PermitUserEnvironment\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*PermitUserEnvironment\s+
      line: PermitUserEnvironment no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27363-1
  - CJIS-5.5.6
  - DISA-STIG-RHEL-07-010460
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_do_not_permit_user_env

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*PermitUserEnvironment\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "PermitUserEnvironment no" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Enable Use of Strict Mode Checking   [ref]

SSHs StrictModes option checks file and ownership permissions in the user's home directory .ssh folder before accepting login. If world- writable permissions are found, logon is rejected.
The default SSH configuration has StrictModes enabled. The appropriate configuration is used if no value is set for StrictModes.
To explicitly enable StrictModes in SSH, add or correct the following line in /etc/ssh/sshd_config: 
StrictModes yes
Rationale:
If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_enable_strictmodes
Identifiers:

CCE-80222-3

References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.1.12
disaCCI-000366
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2
nistAC-6, AC-17(a), CM-6(a)
nist-csfPR.AC-4, PR.DS-5
os-srgSRG-OS-000480-GPOS-00227
stigidRHEL-07-040450
stigrefSV-204600r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Enable Use of Strict Mode Checking
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*StrictModes\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*StrictModes\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*StrictModes\s+
      line: StrictModes yes
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80222-3
  - DISA-STIG-RHEL-07-040450
  - NIST-800-171-3.1.12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_enable_strictmodes

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*StrictModes\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "StrictModes yes" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Enable SSH Warning Banner   [ref]

To enable the warning banner and ensure it is consistent across the system, add or correct the following line in /etc/ssh/sshd_config: 
Banner /etc/issue
Another section contains information on how to create an appropriate system-wide warning banner.
Rationale:
The warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. Alternatively, systems whose ownership should not be obvious should ensure usage of a banner that does not provide easy attribution.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_enable_warning_banner
Identifiers:

CCE-27314-4

References:
cis-csc1, 12, 15, 16
cjis5.5.6
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.9
disaCCI-000048, CCI-000050, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9
isa-62443-2013SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9
iso27001-2013A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3
nistAC-8(a), AC-8(c), AC-17(a), CM-6(a)
nist-csfPR.AC-7
osppFTA_TAB.1
pcidssReq-2.2.4
os-srgSRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088
stigidRHEL-07-040170
stigrefSV-204580r603261_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Enable SSH Warning Banner
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Banner\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Banner\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Banner\s+
      line: Banner /etc/issue
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27314-4
  - CJIS-5.5.6
  - DISA-STIG-RHEL-07-040170
  - NIST-800-171-3.1.9
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-8(a)
  - NIST-800-53-AC-8(c)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_enable_warning_banner

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/ssh/sshd_config" ] ; then
    
    LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config"
else
    touch "/etc/ssh/sshd_config"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config"

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "Banner /etc/issue" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Use Only FIPS 140-2 Validated Ciphers   [ref]

Limit the ciphers to those algorithms which are FIPS-approved. Counter (CTR) mode is also preferred over cipher-block chaining (CBC) mode. The following line in /etc/ssh/sshd_config demonstrates use of FIPS-approved ciphers: 
Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc
The man page sshd_config(5) contains a list of supported ciphers.

Only the following ciphers are FIPS 140-2 certified on Red Hat Enterprise Linux 7:
- aes128-ctr
- aes192-ctr
- aes256-ctr
- aes128-cbc
- aes192-cbc
- aes256-cbc
- 3des-cbc
- rijndael-cbc@lysator.liu.se

Any combination of the above ciphers will pass this check. Official FIPS 140-2 paperwork for Red Hat Enterprise Linux 7 can be found at http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140sp/140sp2630.pdf The rule is parametrized to use the following ciphers: aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se.
Warning:  The system needs to be rebooted for these changes to take effect.
Warning:  System Crypto Modules must be provided by a vendor that undergoes FIPS-140 certifications. FIPS-140 is applicable to all Federal agencies that use cryptographic-based security systems to protect sensitive information in computer and telecommunication systems (including voice systems) as defined in Section 5131 of the Information Technology Management Reform Act of 1996, Public Law 104-106. This standard shall be used in designing and implementing cryptographic modules that Federal departments and agencies operate or are operated for them under contract. See https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.140-2.pdf To meet this, the system has to have cryptographic software provided by a vendor that has undergone this certification. This means providing documentation, test results, design information, and independent third party review by an accredited lab. While open source software is capable of meeting this, it does not meet FIPS-140 unless the vendor submits to this process.
Rationale:
Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and system data may be compromised.
Operating systems utilizing encryption are required to use FIPS-compliant mechanisms for authenticating to cryptographic modules.
FIPS 140-2 is the current standard for validating that mechanisms used to access cryptographic modules utilize authentication that meets industry and government requirements. For government systems, this allows Security Levels 1, 2, 3, or 4 for use on Red Hat Enterprise Linux 7.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_use_approved_ciphers
Identifiers:

CCE-27295-5

References:
cis-csc1, 11, 12, 14, 15, 16, 18, 3, 5, 6, 8, 9
cjis5.5.6
cobit5APO11.04, APO13.01, BAI03.05, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, MEA02.01
cui3.1.13, 3.13.11, 3.13.8
disaCCI-000068, CCI-000366, CCI-000803, CCI-000877, CCI-002890, CCI-003123
hipaa164.308(b)(1), 164.308(b)(2), 164.312(e)(1), 164.312(e)(2)(i), 164.312(e)(2)(ii), 164.314(b)(2)(i)
isa-62443-20094.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.5.1, A.12.6.2, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.18.1.4, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistCM-6(a), AC-17(a), AC-17(2), SC-13, MA-4(6), IA-5(1)(c), SC-12(2), SC-12(3)
nist-csfPR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.AC-7, PR.IP-1, PR.PT-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000033-GPOS-00014, SRG-OS-000120-GPOS-00061, SRG-OS-000125-GPOS-00065, SRG-OS-000250-GPOS-00093, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174
cis4.2.6
pcidss42.2.7

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value sshd_approved_ciphers # promote to variable
  set_fact:
    sshd_approved_ciphers: !!str aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se
  tags:
    - always

- name: Use Only FIPS 140-2 Validated Ciphers
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Ciphers\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Ciphers\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*Ciphers\s+
      line: Ciphers {{ sshd_approved_ciphers }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27295-5
  - CJIS-5.5.6
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.11
  - NIST-800-171-3.13.8
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-MA-4(6)
  - NIST-800-53-SC-12(2)
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SC-13
  - PCI-DSSv4-2.2.7
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_use_approved_ciphers


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

sshd_approved_ciphers='aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se'


# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^Ciphers")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "$sshd_approved_ciphers"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^Ciphers\\>" "/etc/ssh/sshd_config"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^Ciphers\\>.*/$escaped_formatted_output/gi" "/etc/ssh/sshd_config"
else
    if [[ -s "/etc/ssh/sshd_config" ]] && [[ -n "$(tail -c 1 -- "/etc/ssh/sshd_config" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/ssh/sshd_config"
    fi
    cce="CCE-27295-5"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/ssh/sshd_config" >> "/etc/ssh/sshd_config"
    printf '%s\n' "$formatted_output" >> "/etc/ssh/sshd_config"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Use Only FIPS 140-2 Validated MACs   [ref]

Limit the MACs to those hash algorithms which are FIPS-approved. The following line in /etc/ssh/sshd_config demonstrates use of FIPS-approved MACs: 
MACs hmac-sha2-512,hmac-sha2-256,hmac-sha1
The man page sshd_config(5) contains a list of supported MACs.

Only the following message authentication codes are FIPS 140-2 certified on Red Hat Enterprise Linux 7:
- hmac-sha1
- hmac-sha2-256
- hmac-sha2-512
- hmac-sha1-etm@openssh.com
- hmac-sha2-256-etm@openssh.com
- hmac-sha2-512-etm@openssh.com

Any combination of the above MACs will pass this check. Official FIPS 140-2 paperwork for Red Hat Enterprise Linux 7 can be found at http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140sp/140sp2630.pdf The rule is parametrized to use the following MACs: hmac-sha2-512,hmac-sha2-256,hmac-sha1,hmac-sha1-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com.
Warning:  The system needs to be rebooted for these changes to take effect.
Warning:  System Crypto Modules must be provided by a vendor that undergoes FIPS-140 certifications. FIPS-140 is applicable to all Federal agencies that use cryptographic-based security systems to protect sensitive information in computer and telecommunication systems (including voice systems) as defined in Section 5131 of the Information Technology Management Reform Act of 1996, Public Law 104-106. This standard shall be used in designing and implementing cryptographic modules that Federal departments and agencies operate or are operated for them under contract. See https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.140-2.pdf To meet this, the system has to have cryptographic software provided by a vendor that has undergone this certification. This means providing documentation, test results, design information, and independent third party review by an accredited lab. While open source software is capable of meeting this, it does not meet FIPS-140 unless the vendor submits to this process.
Rationale:
DoD Information Systems are required to use FIPS-approved cryptographic hash functions. The only SSHv2 hash algorithms meeting this requirement is SHA2.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_use_approved_macs
Identifiers:

CCE-27455-5

References:
cis-csc1, 12, 13, 15, 16, 5, 8
cobit5APO01.06, APO13.01, DSS01.04, DSS05.02, DSS05.03, DSS05.04, DSS05.07, DSS06.02, DSS06.03
cui3.1.13, 3.13.11, 3.13.8
disaCCI-000068, CCI-000803, CCI-000877, CCI-001453, CCI-003123
hipaa164.308(b)(1), 164.308(b)(2), 164.312(e)(1), 164.312(e)(2)(i), 164.312(e)(2)(ii), 164.314(b)(2)(i)
isa-62443-20094.3.3.5.1, 4.3.3.6.6
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.6, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.11.2.6, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistCM-6(a), AC-17(a), AC-17(2), SC-13, MA-4(6), SC-12(2), SC-12(3)
nist-csfPR.AC-1, PR.AC-3, PR.DS-5, PR.PT-4
os-srgSRG-OS-000125-GPOS-00065, SRG-OS-000250-GPOS-00093, SRG-OS-000394-GPOS-00174
pcidss42.2.7

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value sshd_approved_macs # promote to variable
  set_fact:
    sshd_approved_macs: !!str hmac-sha2-512,hmac-sha2-256,hmac-sha1,hmac-sha1-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com
  tags:
    - always

- name: Use Only FIPS 140-2 Validated MACs
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*MACs\s+
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*MACs\s+
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)^\s*MACs\s+
      line: MACs {{ sshd_approved_macs }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27455-5
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.11
  - NIST-800-171-3.13.8
  - NIST-800-53-AC-17(2)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-MA-4(6)
  - NIST-800-53-SC-12(2)
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SC-13
  - PCI-DSSv4-2.2.7
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_use_approved_macs


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

sshd_approved_macs='hmac-sha2-512,hmac-sha2-256,hmac-sha1,hmac-sha1-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com'


# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^MACs")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "$sshd_approved_macs"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^MACs\\>" "/etc/ssh/sshd_config"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^MACs\\>.*/$escaped_formatted_output/gi" "/etc/ssh/sshd_config"
else
    if [[ -s "/etc/ssh/sshd_config" ]] && [[ -n "$(tail -c 1 -- "/etc/ssh/sshd_config" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/ssh/sshd_config"
    fi
    cce="CCE-27455-5"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "/etc/ssh/sshd_config" >> "/etc/ssh/sshd_config"
    printf '%s\n' "$formatted_output" >> "/etc/ssh/sshd_config"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   System Accounting with auditd   Group contains 10 groups and 70 rules
[ref]   The audit service provides substantial capabilities for recording system activities. By default, the service audits about SELinux AVC denials and certain types of security-relevant events such as system logins, account modifications, and authentication events performed by programs such as sudo. Under its default configuration, auditd has modest disk space requirements, and should not noticeably impact system performance.

NOTE: The Linux Audit daemon auditd can be configured to use the augenrules program to read audit rules files (*.rules) located in /etc/audit/rules.d location and compile them to create the resulting form of the /etc/audit/audit.rules configuration file during the daemon startup (default configuration). Alternatively, the auditd daemon can use the auditctl utility to read audit rules from the /etc/audit/audit.rules configuration file during daemon startup, and load them into the kernel. The expected behavior is configured via the appropriate ExecStartPost directive setting in the /usr/lib/systemd/system/auditd.service configuration file. To instruct the auditd daemon to use the augenrules program to read audit rules (default configuration), use the following setting: 
ExecStartPost=-/sbin/augenrules --load
in the /usr/lib/systemd/system/auditd.service configuration file. In order to instruct the auditd daemon to use the auditctl utility to read audit rules, use the following setting: 
ExecStartPost=-/sbin/auditctl -R /etc/audit/audit.rules
in the /usr/lib/systemd/system/auditd.service configuration file. Refer to [Service] section of the /usr/lib/systemd/system/auditd.service configuration file for further details.

Government networks often have substantial auditing requirements and auditd can be configured to meet these requirements. Examining some example audit records demonstrates how the Linux audit system satisfies common requirements. The following example from Red Hat Enterprise Linux 7 Documentation available at https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html-single/selinux_users_and_administrators_guide/index#sect-Security-Enhanced_Linux-Fixing_Problems-Raw_Audit_Messages shows the substantial amount of information captured in a two typical "raw" audit messages, followed by a breakdown of the most important fields. In this example the message is SELinux-related and reports an AVC denial (and the associated system call) that occurred when the Apache HTTP Server attempted to access the /var/www/html/file1 file (labeled with the samba_share_t type): 
type=AVC msg=audit(1226874073.147:96): avc:  denied  { getattr } for pid=2465 comm="httpd"
path="/var/www/html/file1" dev=dm-0 ino=284133 scontext=unconfined_u:system_r:httpd_t:s0
tcontext=unconfined_u:object_r:samba_share_t:s0 tclass=file

type=SYSCALL msg=audit(1226874073.147:96): arch=40000003 syscall=196 success=no exit=-13
a0=b98df198 a1=bfec85dc a2=54dff4 a3=2008171 items=0 ppid=2463 pid=2465 auid=502 uid=48
gid=48 euid=48 suid=48 fsuid=48 egid=48 sgid=48 fsgid=48 tty=(none) ses=6 comm="httpd"
exe="/usr/sbin/httpd" subj=unconfined_u:system_r:httpd_t:s0 key=(null)
  • msg=audit(1226874073.147:96)
    • The number in parentheses is the unformatted time stamp (Epoch time) for the event, which can be converted to standard time by using the date command.
  • { getattr }
    • The item in braces indicates the permission that was denied. getattr indicates the source process was trying to read the target file's status information. This occurs before reading files. This action is denied due to the file being accessed having the wrong label. Commonly seen permissions include getattr, read, and write.
  • comm="httpd"
    • The executable that launched the process. The full path of the executable is found in the exe= section of the system call (SYSCALL) message, which in this case, is exe="/usr/sbin/httpd".
  • path="/var/www/html/file1"
    • The path to the object (target) the process attempted to access.
  • scontext="unconfined_u:system_r:httpd_t:s0"
    • The SELinux context of the process that attempted the denied action. In this case, it is the SELinux context of the Apache HTTP Server, which is running in the httpd_t domain.
  • tcontext="unconfined_u:object_r:samba_share_t:s0"
    • The SELinux context of the object (target) the process attempted to access. In this case, it is the SELinux context of file1. Note: the samba_share_t type is not accessible to processes running in the httpd_t domain.
  • From the system call (SYSCALL) message, two items are of interest:
    • success=no: indicates whether the denial (AVC) was enforced or not. success=no indicates the system call was not successful (SELinux denied access). success=yes indicates the system call was successful - this can be seen for permissive domains or unconfined domains, such as initrc_t and kernel_t.
    • exe="/usr/sbin/httpd": the full path to the executable that launched the process, which in this case, is exe="/usr/sbin/httpd".
Group   Configure auditd Rules for Comprehensive Auditing   Group contains 8 groups and 66 rules
[ref]   The auditd program can perform comprehensive monitoring of system activity. This section describes recommended configuration settings for comprehensive auditing, but a full description of the auditing system's capabilities is beyond the scope of this guide. The mailing list linux-audit@redhat.com exists to facilitate community discussion of the auditing system.

The audit subsystem supports extensive collection of events, including:
  • Tracing of arbitrary system calls (identified by name or number) on entry or exit.
  • Filtering by PID, UID, call success, system call argument (with some limitations), etc.
  • Monitoring of specific files for modifications to the file's contents or metadata.

Auditing rules at startup are controlled by the file /etc/audit/audit.rules. Add rules to it to meet the auditing requirements for your organization. Each line in /etc/audit/audit.rules represents a series of arguments that can be passed to auditctl and can be individually tested during runtime. See documentation in /usr/share/doc/audit-VERSION and in the related man pages for more details.

If copying any example audit rulesets from /usr/share/doc/audit-VERSION, be sure to comment out the lines containing arch= which are not appropriate for your system's architecture. Then review and understand the following rules, ensuring rules are activated as needed for the appropriate architecture.

After reviewing all the rules, reading the following sections, and editing as needed, the new rules can be activated as follows: 
$ sudo service auditd restart
Group   Record Events that Modify the System's Discretionary Access Controls   Group contains 13 rules
[ref]   At a minimum, the audit system should collect file permission changes for all users and root. Note that the "-F arch=b32" lines should be present even on a 64 bit system. These commands identify system calls for auditing. Even if the system is 64 bit it can still execute 32 bit system calls. Additionally, these rules can be configured in a number of ways while still achieving the desired effect. An example of this is that the "-S" calls could be split up and placed on separate lines, however, this is less efficient. Add the following to /etc/audit/audit.rules: 
-a always,exit -F arch=b32 -S chmod,fchmod,fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
    -a always,exit -F arch=b32 -S chown,fchown,fchownat,lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
    -a always,exit -F arch=b32 -S setxattr,lsetxattr,fsetxattr,removexattr,lremovexattr,fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If your system is 64 bit then these lines should be duplicated and the arch=b32 replaced with arch=b64 as follows: 
-a always,exit -F arch=b64 -S chmod,fchmod,fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
    -a always,exit -F arch=b64 -S chown,fchown,fchownat,lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
    -a always,exit -F arch=b64 -S setxattr,lsetxattr,fsetxattr,removexattr,lremovexattr,fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod

Rule   Record Events that Modify the System's Discretionary Access Controls - chmod   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chmod
Identifiers:

CCE-27339-1

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030410
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204521r809772_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27339-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit chmod tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27339-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for chmod for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of chmod in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of chmod in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-27339-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for chmod for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of chmod in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of chmod in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-27339-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="chmod"
	KEY="perm_mod"
	SYSCALL_GROUPING="chmod fchmod fchmodat"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - chown   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chown
Identifiers:

CCE-27364-9

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030370
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204517r809570_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27364-9
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit chown tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27364-9
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for chown for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of chown in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of chown in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-27364-9
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for chown for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of chown in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - chown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of chown in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-27364-9
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_chown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="chown"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - fchmod   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmod
Identifiers:

CCE-27393-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030410
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204521r809772_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27393-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit fchmod tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27393-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchmod for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmod in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmod in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27393-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchmod for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmod in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmod
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmod in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27393-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmod
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchmod"
	KEY="perm_mod"
	SYSCALL_GROUPING="chmod fchmod fchmodat"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - fchmodat   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmodat
Identifiers:

CCE-27388-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030410
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204521r809772_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27388-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmodat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit fchmodat tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27388-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmodat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmodat
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmodat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmodat
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmodat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27388-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmodat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchmodat for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmodat
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmodat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchmodat
      syscall_grouping:
      - chmod
      - fchmod
      - fchmodat

  - name: Check existence of fchmodat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27388-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030410
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchmodat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchmodat"
	KEY="perm_mod"
	SYSCALL_GROUPING="chmod fchmod fchmodat"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - fchown   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchown
Identifiers:

CCE-27356-5

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030370
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204517r809570_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27356-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit fchown tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27356-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchown for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchown in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchown in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27356-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchown for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchown in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchown in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27356-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchown"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - fchownat   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchownat
Identifiers:

CCE-27387-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030370
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204517r809570_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27387-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchownat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit fchownat tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27387-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchownat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchownat for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchownat
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchownat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchownat
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchownat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27387-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchownat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fchownat for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchownat
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchownat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fchownat
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of fchownat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27387-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fchownat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fchownat"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - fremovexattr   [ref]

At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fremovexattr
Identifiers:

CCE-27353-2

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000466-GPOS-00210, SRG-OS-000468-GPOS-00212, SRG-OS-000064-GPOS-00033
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000499-CTR-001255
stigidRHEL-07-030440
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204524r809775_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27353-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit fremovexattr tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27353-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fremovexattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fremovexattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27353-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fremovexattr for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fremovexattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fremovexattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27353-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fremovexattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - fsetxattr   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fsetxattr
Identifiers:

CCE-27389-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000466-GPOS-00210, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000064-GPOS-00033
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030440
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204524r809775_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27389-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit fsetxattr tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27389-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fsetxattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fsetxattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27389-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for fsetxattr for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fsetxattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - fsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of fsetxattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27389-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_fsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="fsetxattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - lchown   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lchown
Identifiers:

CCE-27083-5

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203, SRG-OS-000474-GPOS-00219
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030370
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204517r809570_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27083-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit lchown tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27083-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for lchown for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of lchown in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of lchown in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-27083-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for lchown for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of lchown in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lchown
      syscall_grouping:
      - chown
      - fchown
      - fchownat
      - lchown

  - name: Check existence of lchown in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-27083-5
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030370
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lchown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="lchown"
	KEY="perm_mod"
	SYSCALL_GROUPING="chown fchown fchownat lchown"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - lremovexattr   [ref]

At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lremovexattr
Identifiers:

CCE-27410-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000466-GPOS-00210, SRG-OS-000064-GPOS-00033
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000499-CTR-001255, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030440
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204524r809775_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27410-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit lremovexattr tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27410-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lremovexattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lremovexattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27410-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for lremovexattr for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lremovexattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lremovexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lremovexattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27410-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lremovexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="lremovexattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - lsetxattr   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lsetxattr
Identifiers:

CCE-27280-7

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000466-GPOS-00210, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000064-GPOS-00033
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030440
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204524r809775_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27280-7
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit lsetxattr tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27280-7
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lsetxattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lsetxattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27280-7
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for lsetxattr for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lsetxattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - lsetxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of lsetxattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27280-7
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_lsetxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="lsetxattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - removexattr   [ref]

At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_removexattr
Identifiers:

CCE-27367-2

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000458-GPOS-00203, SRG-OS-000462-GPOS-00206, SRG-OS-000463-GPOS-00207, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000474-GPOS-00219, SRG-OS-000466-GPOS-00210, SRG-OS-000064-GPOS-00033
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000499-CTR-001255, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030440
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204524r809775_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27367-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_removexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit removexattr tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27367-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_removexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for removexattr for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - removexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of removexattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - removexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of removexattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27367-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_removexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for removexattr for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - removexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of removexattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - removexattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of removexattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27367-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_removexattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="removexattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Discretionary Access Controls - setxattr   [ref]

At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_dac_modification_setxattr
Identifiers:

CCE-27213-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000466-GPOS-00210, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203
app-srg-ctrSRG-APP-000091-CTR-000160, SRG-APP-000492-CTR-001220, SRG-APP-000493-CTR-001225, SRG-APP-000494-CTR-001230, SRG-APP-000500-CTR-001260, SRG-APP-000507-CTR-001295, SRG-APP-000495-CTR-001235
stigidRHEL-07-030440
anssiR73
cis5.2.3.9
pcidss410.3.4
stigrefSV-204524r809775_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27213-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_setxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit setxattr tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27213-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_setxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for setxattr for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - setxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of setxattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - setxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of setxattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27213-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_setxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for setxattr for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - setxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of setxattr in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - setxattr
      syscall_grouping:
      - fremovexattr
      - lremovexattr
      - removexattr
      - fsetxattr
      - lsetxattr
      - setxattr

  - name: Check existence of setxattr in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27213-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030440
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_dac_modification_setxattr
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="setxattr"
	KEY="perm_mod"
	SYSCALL_GROUPING="fremovexattr lremovexattr removexattr fsetxattr lsetxattr setxattr"

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Record Execution Attempts to Run SELinux Privileged Commands   Group contains 4 rules
[ref]   At a minimum, the audit system should collect the execution of SELinux privileged commands for all users and root.

Rule   Record Any Attempts to Run chcon   [ref]

At a minimum, the audit system should collect any execution attempt of the chcon command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/chcon -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F path=/usr/bin/chcon -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_execution_chcon
Identifiers:

CCE-80393-2

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030580
cis5.2.3.15
stigrefSV-204538r861020_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80393-2
  - DISA-STIG-RHEL-07-030580
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_chcon
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/chcon
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/chcon -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chcon -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chcon -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/chcon -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/chcon -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chcon -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80393-2
  - DISA-STIG-RHEL-07-030580
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_chcon
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/chcon -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Any Attempts to Run restorecon   [ref]

At a minimum, the audit system should collect any execution attempt of the restorecon command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/restorecon -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F path=/usr/sbin/restorecon -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_execution_restorecon
Identifiers:

CCE-80394-0

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000392-GPOS-00172, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80394-0
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_restorecon
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/restorecon
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/restorecon -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/restorecon -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/restorecon
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/restorecon -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/restorecon -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/restorecon
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80394-0
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_restorecon
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/restorecon -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Any Attempts to Run semanage   [ref]

At a minimum, the audit system should collect any execution attempt of the semanage command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/semanage -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F path=/usr/sbin/semanage -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_execution_semanage
Identifiers:

CCE-80391-6

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250
stigidRHEL-07-030560
stigrefSV-204536r861014_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80391-6
  - DISA-STIG-RHEL-07-030560
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_semanage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/semanage
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/semanage -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/semanage -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/semanage -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/semanage -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/semanage -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/semanage -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80391-6
  - DISA-STIG-RHEL-07-030560
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_semanage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/semanage -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Any Attempts to Run setsebool   [ref]

At a minimum, the audit system should collect any execution attempt of the setsebool command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/setsebool -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F path=/usr/sbin/setsebool -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_execution_setsebool
Identifiers:

CCE-80392-4

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000463-GPOS-00207, SRG-OS-000465-GPOS-00209
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250
stigidRHEL-07-030570
stigrefSV-204537r861017_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80392-4
  - DISA-STIG-RHEL-07-030570
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_setsebool
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/setsebool
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/setsebool -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/setsebool -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/setsebool -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/setsebool -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/setsebool -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/setsebool -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80392-4
  - DISA-STIG-RHEL-07-030570
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_execution_setsebool
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/setsebool -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Record File Deletion Events by User   Group contains 5 rules
[ref]   At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S rmdir,unlink,unlinkat,rename,renameat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S rmdir,unlink,unlinkat,rename,renameat -F auid>=1000 -F auid!=unset -F key=delete

Rule   Ensure auditd Collects File Deletion Events by User - rename   [ref]

At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S rename -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S rename -F auid>=1000 -F auid!=unset -F key=delete
Rationale:
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_rename
Identifiers:

CCE-80995-4

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-000366, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030910
anssiR73
cis5.2.3.13
pcidss410.2.1.7
stigrefSV-204572r853985_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80995-4
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rename
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit rename tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80995-4
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rename
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for rename for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rename
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rename in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rename
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rename in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-80995-4
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rename
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for rename for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rename
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rename in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rename
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rename in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-80995-4
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rename
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="rename"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects File Deletion Events by User - renameat   [ref]

At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S renameat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S renameat -F auid>=1000 -F auid!=unset -F key=delete
Rationale:
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_renameat
Identifiers:

CCE-80413-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-000366, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030910
anssiR73
cis5.2.3.13
pcidss410.2.1.7
stigrefSV-204572r853985_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80413-8
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_renameat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit renameat tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80413-8
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_renameat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for renameat for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - renameat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of renameat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - renameat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of renameat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80413-8
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_renameat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for renameat for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - renameat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of renameat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - renameat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of renameat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80413-8
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_renameat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="renameat"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects File Deletion Events by User - rmdir   [ref]

At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S rmdir -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S rmdir -F auid>=1000 -F auid!=unset -F key=delete
Rationale:
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_rmdir
Identifiers:

CCE-80412-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-000366, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030910
anssiR73
pcidss410.2.1.7
stigrefSV-204572r853985_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80412-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rmdir
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit rmdir tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80412-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rmdir
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for rmdir for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rmdir
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rmdir in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rmdir
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rmdir in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-80412-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rmdir
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for rmdir for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rmdir
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rmdir in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - rmdir
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of rmdir in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-80412-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_rmdir
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="rmdir"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects File Deletion Events by User - unlinkat   [ref]

At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S unlinkat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S unlinkat -F auid>=1000 -F auid!=unset -F key=delete
Rationale:
Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events_unlinkat
Identifiers:

CCE-80662-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-000366, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.4, A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.1.1, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.MA-2, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210, SRG-OS-000467-GPOS-00211, SRG-OS-000468-GPOS-00212
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030910
anssiR73
cis5.2.3.13
pcidss410.2.1.7
stigrefSV-204572r853985_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80662-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_unlinkat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit unlinkat tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80662-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_unlinkat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - unlinkat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of unlinkat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - unlinkat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of unlinkat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80662-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_unlinkat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for unlinkat for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - unlinkat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of unlinkat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/delete.rules
    set_fact: audit_file="/etc/audit/rules.d/delete.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - unlinkat
      syscall_grouping:
      - unlink
      - unlinkat
      - rename
      - renameat
      - rmdir

  - name: Check existence of unlinkat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=delete
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80662-0
  - DISA-STIG-RHEL-07-030910
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_file_deletion_events_unlinkat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="unlinkat"
	KEY="delete"
	SYSCALL_GROUPING="unlink unlinkat rename renameat rmdir"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Record Unauthorized Access Attempts Events to Files (unsuccessful)   Group contains 6 rules
[ref]   At a minimum, the audit system should collect unauthorized file accesses for all users and root. Note that the "-F arch=b32" lines should be present even on a 64 bit system. These commands identify system calls for auditing. Even if the system is 64 bit it can still execute 32 bit system calls. Additionally, these rules can be configured in a number of ways while still achieving the desired effect. An example of this is that the "-S" calls could be split up and placed on separate lines, however, this is less efficient. Add the following to /etc/audit/audit.rules: 
-a always,exit -F arch=b32 -S creat,open,openat,open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
    -a always,exit -F arch=b32 -S creat,open,openat,open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If your system is 64 bit then these lines should be duplicated and the arch=b32 replaced with arch=b64 as follows: 
-a always,exit -F arch=b64 -S creat,open,openat,open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
    -a always,exit -F arch=b64 -S creat,open,openat,open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access

Rule   Record Unsuccessful Access Attempts to Files - creat   [ref]

At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_creat
Identifiers:

CCE-80385-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.4, Req-10.2.1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030510
anssiR73
cis5.2.3.7
stigrefSV-204531r853917_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80385-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_creat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit creat tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80385-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_creat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for creat EACCES for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-80385-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_creat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for creat EACCES for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-80385-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_creat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for creat EPERM for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-80385-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_creat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for creat EPERM for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - creat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of creat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-80385-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_creat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="creat"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Unsuccessful Access Attempts to Files - ftruncate   [ref]

At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_ftruncate
Identifiers:

CCE-80390-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.4, Req-10.2.1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030510
anssiR73
cis5.2.3.7
stigrefSV-204531r853917_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80390-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_ftruncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit ftruncate tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80390-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_ftruncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EACCES for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80390-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_ftruncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EACCES for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80390-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_ftruncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EPERM for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80390-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_ftruncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for ftruncate EPERM for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - ftruncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of ftruncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80390-8
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_ftruncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="ftruncate"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Unsuccessful Access Attempts to Files - open   [ref]

At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open
Identifiers:

CCE-80386-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.4, Req-10.2.1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030510
anssiR73
cis5.2.3.7
stigrefSV-204531r853917_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80386-6
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit open tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80386-6
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open EACCES for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-80386-6
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open EACCES for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-80386-6
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open EPERM for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  tags:
  - CCE-80386-6
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open EPERM for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - not ( ansible_architecture == "aarch64" )
  - audit_arch == "b64"
  tags:
  - CCE-80386-6
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ! ( grep -q aarch64 /proc/sys/kernel/osrelease ); }; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="open"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Unsuccessful Access Attempts to Files - open_by_handle_at   [ref]

At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_open_by_handle_at
Identifiers:

CCE-80388-2

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.4, Req-10.2.1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030510
stigrefSV-204531r853917_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80388-2
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open_by_handle_at
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit open_by_handle_at tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80388-2
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open_by_handle_at
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EACCES for 32bit
    platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80388-2
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open_by_handle_at
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EACCES for 64bit
    platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80388-2
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open_by_handle_at
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EPERM for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80388-2
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open_by_handle_at
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for open_by_handle_at EPERM for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - open_by_handle_at
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of open_by_handle_at in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80388-2
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_open_by_handle_at
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="open_by_handle_at"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Unsuccessful Access Attempts to Files - openat   [ref]

At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_openat
Identifiers:

CCE-80387-4

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.4, Req-10.2.1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030510
anssiR73
cis5.2.3.7
stigrefSV-204531r853917_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80387-4
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_openat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit openat tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80387-4
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_openat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for openat EACCES for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80387-4
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_openat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for openat EACCES for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80387-4
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_openat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for openat EPERM for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80387-4
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_openat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for openat EPERM for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - openat
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of openat in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80387-4
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_openat
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="openat"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Unsuccessful Access Attempts to Files - truncate   [ref]

At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines: 
-a always,exit -F arch=b64 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
Warning:  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Rationale:
Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification_truncate
Identifiers:

CCE-80389-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.4, Req-10.2.1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030510
anssiR73
cis5.2.3.7
stigrefSV-204531r853917_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80389-0
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_truncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit truncate tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80389-0
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_truncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for truncate EACCES for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80389-0
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_truncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for truncate EACCES for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EACCES -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EACCES -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EACCES
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80389-0
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_truncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for truncate EPERM for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80389-0
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_truncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for truncate EPERM for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/access.rules
    set_fact: audit_file="/etc/audit/rules.d/access.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - truncate
      syscall_grouping:
      - creat
      - ftruncate
      - truncate
      - open
      - openat
      - open_by_handle_at

  - name: Check existence of truncate in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F exit=-EPERM -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F exit=-EPERM -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F exit=-EPERM
        -F auid>=1000 -F auid!=unset -F key=access
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80389-0
  - DISA-STIG-RHEL-07-030510
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1
  - PCI-DSS-Req-10.2.4
  - audit_rules_unsuccessful_file_modification_truncate
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL="truncate"
KEY="access"
SYSCALL_GROUPING="creat ftruncate truncate open openat open_by_handle_at"

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EACCES"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F exit=-EPERM"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Record Information on Kernel Modules Loading and Unloading   Group contains 2 rules
[ref]   To capture kernel module loading and unloading events, use following lines, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit: 
-a always,exit -F arch=ARCH -S init_module,delete_module -F key=modules
Place to add the lines depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the lines to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the lines to file /etc/audit/audit.rules.

Rule   Ensure auditd Collects Information on Kernel Module Unloading - delete_module   [ref]

To capture kernel module unloading events, use following line, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit: 
-a always,exit -F arch=ARCH -S delete_module -F auid>=1000 -F auid!=unset -F key=modules
Place to add the line depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the line to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the line to file /etc/audit/audit.rules.
Rationale:
The removal of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading_delete
Identifiers:

CCE-80415-3

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-GPOS-00216, SRG-OS-000477-GPOS-00222
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000504-CTR-001280
stigidRHEL-07-030830
anssiR73
cis5.2.3.19
stigrefSV-204562r833175_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80415-3
  - DISA-STIG-RHEL-07-030830
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_delete
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set architecture for audit delete_module tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80415-3
  - DISA-STIG-RHEL-07-030830
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_delete
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Perform remediation of Audit rules for delete_module for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - delete_module
      syscall_grouping: []

  - name: Check existence of delete_module in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/module-change.rules
    set_fact: audit_file="/etc/audit/rules.d/module-change.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - delete_module
      syscall_grouping: []

  - name: Check existence of delete_module in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80415-3
  - DISA-STIG-RHEL-07-030830
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_delete
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Perform remediation of Audit rules for delete_module for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - delete_module
      syscall_grouping: []

  - name: Check existence of delete_module in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/module-change.rules
    set_fact: audit_file="/etc/audit/rules.d/module-change.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - delete_module
      syscall_grouping: []

  - name: Check existence of delete_module in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80415-3
  - DISA-STIG-RHEL-07-030830
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_delete
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
# Note: 32-bit and 64-bit kernel syscall numbers not always line up =>
#       it's required on a 64-bit system to check also for the presence
#       of 32-bit's equivalent of the corresponding rule.
#       (See `man 7 audit.rules` for details )
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	
	SYSCALL="delete_module"
	KEY="modules"
	SYSCALL_GROUPING="delete_module"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20delete_module%20-k%20module-change%0A-a%20always%2Cexit%20-F%20arch%3Db64%20-S%20delete_module%20-k%20module-change%0A
        mode: 0600
        path: /etc/audit/rules.d/75-kernel-module-loading-delete.rules
        overwrite: true

Rule   Ensure auditd Collects Information on Kernel Module Loading - init_module   [ref]

To capture kernel module loading events, use following line, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit: 
-a always,exit -F arch=ARCH -S init_module -F auid>=1000 -F auid!=unset -F key=modules
Place to add the line depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the line to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the line to file /etc/audit/audit.rules.
Rationale:
The addition of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading_init
Identifiers:

CCE-80414-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000471-GPOS-00216, SRG-OS-000477-GPOS-00222
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000504-CTR-001280
stigidRHEL-07-030820
anssiR73
cis5.2.3.19
stigrefSV-204560r833172_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80414-6
  - DISA-STIG-RHEL-07-030820
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_init
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set architecture for audit init_module tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-80414-6
  - DISA-STIG-RHEL-07-030820
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_init
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Perform remediation of Audit rules for init_module for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - init_module
      syscall_grouping:
      - init_module
      - finit_module

  - name: Check existence of init_module in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/module-change.rules
    set_fact: audit_file="/etc/audit/rules.d/module-change.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - init_module
      syscall_grouping:
      - init_module
      - finit_module

  - name: Check existence of init_module in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80414-6
  - DISA-STIG-RHEL-07-030820
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_init
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Perform remediation of Audit rules for init_module for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - init_module
      syscall_grouping:
      - init_module
      - finit_module

  - name: Check existence of init_module in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/module-change.rules
    set_fact: audit_file="/etc/audit/rules.d/module-change.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - init_module
      syscall_grouping:
      - init_module
      - finit_module

  - name: Check existence of init_module in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=module-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-80414-6
  - DISA-STIG-RHEL-07-030820
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - audit_rules_kernel_module_loading_init
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
# Note: 32-bit and 64-bit kernel syscall numbers not always line up =>
#       it's required on a 64-bit system to check also for the presence
#       of 32-bit's equivalent of the corresponding rule.
#       (See `man 7 audit.rules` for details )
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	
	SYSCALL="init_module"
	KEY="modules"
	SYSCALL_GROUPING="init_module finit_module"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20init_module%20-k%20module-change%0A-a%20always%2Cexit%20-F%20arch%3Db64%20-S%20init_module%20-k%20module-change%0A
        mode: 0600
        path: /etc/audit/rules.d/75-kernel-module-loading-init.rules
        overwrite: true
Group   Record Attempts to Alter Logon and Logout Events   Group contains 3 rules
Group   Record Information on the Use of Privileged Commands   Group contains 16 rules
[ref]   At a minimum, the audit system should collect the execution of privileged commands for all users and root.

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - chage   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_chage
Identifiers:

CCE-80398-1

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000468-GPOS-00212, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235, SRG-APP-000501-CTR-001265, SRG-APP-000502-CTR-001270
stigidRHEL-07-030660
stigrefSV-204545r861035_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80398-1
  - DISA-STIG-RHEL-07-030660
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_chage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/chage
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chage -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chage -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chage -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80398-1
  - DISA-STIG-RHEL-07-030660
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_chage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/chage -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - chsh   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/chsh -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/chsh -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_chsh
Identifiers:

CCE-80404-7

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030720
stigrefSV-204551r861050_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80404-7
  - DISA-STIG-RHEL-07-030720
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_chsh
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/chsh
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/chsh -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/chsh -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chsh -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/chsh -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/chsh -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/chsh -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80404-7
  - DISA-STIG-RHEL-07-030720
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_chsh
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/chsh -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - crontab   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/crontab -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/crontab -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_crontab
Identifiers:

CCE-80410-4

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030800
stigrefSV-204557r861068_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80410-4
  - DISA-STIG-RHEL-07-030800
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/crontab
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/crontab -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/crontab -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/crontab -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/crontab -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/crontab -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/crontab -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80410-4
  - DISA-STIG-RHEL-07-030800
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/crontab -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - gpasswd   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/gpasswd -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/gpasswd -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_gpasswd
Identifiers:

CCE-80397-3

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235
stigidRHEL-07-030650
stigrefSV-204544r861032_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80397-3
  - DISA-STIG-RHEL-07-030650
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_gpasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/gpasswd
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/gpasswd -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/gpasswd -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/gpasswd -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/gpasswd -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/gpasswd -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/gpasswd -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80397-3
  - DISA-STIG-RHEL-07-030650
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_gpasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/gpasswd -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - newgrp   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/newgrp -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/newgrp -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_newgrp
Identifiers:

CCE-80403-9

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000169, CCI-000135, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235
stigidRHEL-07-030710
stigrefSV-204550r861047_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80403-9
  - DISA-STIG-RHEL-07-030710
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_newgrp
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/newgrp
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/newgrp -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/newgrp -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newgrp -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/newgrp -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/newgrp -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/newgrp -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80403-9
  - DISA-STIG-RHEL-07-030710
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_newgrp
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/newgrp -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - pam_timestamp_check   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/pam_timestamp_check
-F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/sbin/pam_timestamp_check
-F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_pam_timestamp_check
Identifiers:

CCE-80411-2

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235
stigidRHEL-07-030810
stigrefSV-204558r833166_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80411-2
  - DISA-STIG-RHEL-07-030810
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_pam_timestamp_check
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/pam_timestamp_check
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/pam_timestamp_check -F perm=x -F auid>=1000 -F auid!=unset
        (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/pam_timestamp_check
        -F perm=x -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/pam_timestamp_check
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/pam_timestamp_check -F perm=x -F auid>=1000 -F auid!=unset
        (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/pam_timestamp_check -F perm=x -F auid>=1000
        -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/pam_timestamp_check
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80411-2
  - DISA-STIG-RHEL-07-030810
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_pam_timestamp_check
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/pam_timestamp_check -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - passwd   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/passwd -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/passwd -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_passwd
Identifiers:

CCE-80395-7

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235
stigidRHEL-07-030630
stigrefSV-204542r861026_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80395-7
  - DISA-STIG-RHEL-07-030630
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/passwd
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/passwd -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/passwd -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/passwd -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/passwd -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/passwd -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/passwd -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80395-7
  - DISA-STIG-RHEL-07-030630
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/passwd -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - postdrop   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/postdrop -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/sbin/postdrop -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_postdrop
Identifiers:

CCE-80406-2

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030760
stigrefSV-204554r861059_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80406-2
  - DISA-STIG-RHEL-07-030760
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_postdrop
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/postdrop
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/postdrop -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/postdrop -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/postdrop -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/postdrop -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/postdrop -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/postdrop -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80406-2
  - DISA-STIG-RHEL-07-030760
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_postdrop
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/postdrop -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - postqueue   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/postqueue -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/sbin/postqueue -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_postqueue
Identifiers:

CCE-80407-0

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030770
stigrefSV-204555r861062_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80407-0
  - DISA-STIG-RHEL-07-030770
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_postqueue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/postqueue
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/postqueue -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/postqueue -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/postqueue -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/postqueue -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/postqueue -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/postqueue -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80407-0
  - DISA-STIG-RHEL-07-030770
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_postqueue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/postqueue -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - ssh-keysign   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_ssh_keysign
Identifiers:

CCE-80408-8

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235
stigidRHEL-07-030780
stigrefSV-204556r861065_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80408-8
  - DISA-STIG-RHEL-07-030780
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_ssh_keysign
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/libexec/openssh/ssh-keysign
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000 -F auid!=unset
        (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/libexec/openssh/ssh-keysign
        -F perm=x -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/libexec/openssh/ssh-keysign
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000 -F auid!=unset
        (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000
        -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/libexec/openssh/ssh-keysign
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80408-8
  - DISA-STIG-RHEL-07-030780
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_ssh_keysign
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/libexec/openssh/ssh-keysign -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - su   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/su -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/su -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_su
Identifiers:

CCE-80400-5

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000064-GPOS-0003, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030680
stigrefSV-204547r861041_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80400-5
  - DISA-STIG-RHEL-07-030680
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_su
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/su
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/su -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/su -F perm=x -F auid>=1000
        -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/su -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/su -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/su -F perm=x -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/su -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80400-5
  - DISA-STIG-RHEL-07-030680
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_su
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/su -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - sudo   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/sudo -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/sudo -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_sudo
Identifiers:

CCE-80401-3

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000466-GPOS-00210
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255
stigidRHEL-07-030690
anssiR33
stigrefSV-204548r861044_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80401-3
  - DISA-STIG-RHEL-07-030690
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_sudo
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/sudo
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/sudo -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/sudo -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudo -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/sudo -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/sudo -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudo -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80401-3
  - DISA-STIG-RHEL-07-030690
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_sudo
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/sudo -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - sudoedit   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/sudoedit -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_sudoedit
Identifiers:

CCE-80402-1

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80402-1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_sudoedit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/sudoedit
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/sudoedit -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/sudoedit -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudoedit -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/sudoedit -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/sudoedit -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/sudoedit -F
        perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80402-1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_sudoedit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/sudoedit -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - umount   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/bin/umount -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/bin/umount -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_umount
Identifiers:

CCE-80405-4

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000169, CCI-000135, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085
stigidRHEL-07-030750
stigrefSV-204553r861056_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80405-4
  - DISA-STIG-RHEL-07-030750
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_umount
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/bin/umount
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/umount -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/bin/umount -F perm=x -F
        auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/umount -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/bin/umount -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/bin/umount -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/bin/umount -F perm=x
        -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80405-4
  - DISA-STIG-RHEL-07-030750
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_umount
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/bin/umount -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - unix_chkpwd   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/unix_chkpwd -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/sbin/unix_chkpwd -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_unix_chkpwd
Identifiers:

CCE-80396-5

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3, CIP-007-3 R6.5
nistAC-2(4), AU-2(d), AU-3, AU-3.1, AU-12(a), AU-12(c), AU-12.1(ii), AU-12.1(iv), AC-6(9), CM-6(a), MA-4(1)(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000029-CTR-000085, SRG-APP-000495-CTR-001235
stigidRHEL-07-030640
stigrefSV-204543r861029_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80396-5
  - DISA-STIG-RHEL-07-030640
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(a)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-12.1(ii)
  - NIST-800-53-AU-12.1(iv)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-AU-3
  - NIST-800-53-AU-3.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-MA-4(1)(a)
  - audit_rules_privileged_commands_unix_chkpwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/unix_chkpwd
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/unix_chkpwd -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/unix_chkpwd -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/unix_chkpwd
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/unix_chkpwd -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/unix_chkpwd -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/unix_chkpwd
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80396-5
  - DISA-STIG-RHEL-07-030640
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(a)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-12.1(ii)
  - NIST-800-53-AU-12.1(iv)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-AU-3
  - NIST-800-53-AU-3.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-MA-4(1)(a)
  - audit_rules_privileged_commands_unix_chkpwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/unix_chkpwd -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure auditd Collects Information on the Use of Privileged Commands - userhelper   [ref]

At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F path=/usr/sbin/userhelper -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules: 
-a always,exit -F path=/usr/sbin/userhelper -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
Rationale:
Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_privileged_commands_userhelper
Identifiers:

CCE-80399-9

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
osppFAU_GEN.1.1.c
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030670
stigrefSV-204546r861038_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80399-9
  - DISA-STIG-RHEL-07-030670
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_userhelper
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for /usr/sbin/userhelper
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/userhelper -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/privileged.rules
    set_fact: audit_file="/etc/audit/rules.d/privileged.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F path=/usr/sbin/userhelper -F perm=x
        -F auid>=1000 -F auid!=unset (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/userhelper
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls: []
      syscall_grouping: []

  - name: Check existence of  in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit(( -S |,)\w+)*(( -S |,){{ item }})+(( -S |,)\w+)* -F
        path=/usr/sbin/userhelper -F perm=x -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit)(?=.*(?:(?:-S |,)(?:{{ syscalls_found | join("|") }}))\b)((?:(
        -S |,)\w+)+)( -F path=/usr/sbin/userhelper -F perm=x -F auid>=1000 -F auid!=unset
        (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit{{ syscalls | join(',') }} -F path=/usr/sbin/userhelper
        -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80399-9
  - DISA-STIG-RHEL-07-030670
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - audit_rules_privileged_commands_userhelper
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

ACTION_ARCH_FILTERS="-a always,exit"
OTHER_FILTERS="-F path=/usr/sbin/userhelper -F perm=x"
AUID_FILTERS="-F auid>=1000 -F auid!=unset"
SYSCALL=""
KEY="privileged"
SYSCALL_GROUPING=""
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Records Events that Modify Date and Time Information   Group contains 5 rules
[ref]   Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time. All changes to the system time should be audited.

Rule   Record attempts to alter time through adjtimex   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S adjtimex -F key=audit_time_rules
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S adjtimex -F key=audit_time_rules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S adjtimex -F key=audit_time_rules
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S adjtimex -F key=audit_time_rules
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined syscalls: 
-a always,exit -F arch=b64 -S adjtimex,settimeofday -F key=audit_time_rules
Rationale:
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_time_adjtimex
Identifiers:

CCE-27290-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-001487, CCI-000169
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.4.2.b
anssiR73
cis5.2.3.4
pcidss410.6.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27290-6
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_adjtimex
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set architecture for audit tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27290-6
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_adjtimex
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for adjtimex for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - adjtimex
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of adjtimex in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_time_rules.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_time_rules.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - adjtimex
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of adjtimex in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27290-6
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_adjtimex
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for adjtimex for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - adjtimex
      syscall_grouping:
      - adjtimex
      - settimeofday

  - name: Check existence of adjtimex in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_time_rules.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_time_rules.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - adjtimex
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of adjtimex in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27290-6
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_adjtimex
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
    # Create expected audit group and audit rule form for particular system call & architecture
    if [ ${ARCH} = "b32" ]
    then
        ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
        # stime system call is known at 32-bit arch (see e.g "$ ausyscall i386 stime" 's output)
        # so append it to the list of time group system calls to be audited
        SYSCALL="adjtimex settimeofday stime"
        SYSCALL_GROUPING="adjtimex settimeofday stime"
    elif [ ${ARCH} = "b64" ]
    then
        ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
        # stime system call isn't known at 64-bit arch (see "$ ausyscall x86_64 stime" 's output)
        # therefore don't add it to the list of time group system calls to be audited
        SYSCALL="adjtimex settimeofday"
        SYSCALL_GROUPING="adjtimex settimeofday"
    fi
    OTHER_FILTERS=""
    AUID_FILTERS=""
    KEY="audit_time_rules"
    # Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
    unset syscall_a
    unset syscall_grouping
    unset syscall_string
    unset syscall
    unset file_to_edit
    unset rule_to_edit
    unset rule_syscalls_to_edit
    unset other_string
    unset auid_string
    unset full_rule

    # Load macro arguments into arrays
    read -a syscall_a <<< $SYSCALL
    read -a syscall_grouping <<< $SYSCALL_GROUPING

    # Create a list of audit *.rules files that should be inspected for presence and correctness
    # of a particular audit rule. The scheme is as follows:
    #
    # -----------------------------------------------------------------------------------------
    #  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
    # -----------------------------------------------------------------------------------------
    #        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
    # -----------------------------------------------------------------------------------------
    #        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
    #        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
    # -----------------------------------------------------------------------------------------
    #
    files_to_inspect=()

    # If audit tool is 'augenrules', then check if the audit rule is defined
    # If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
    # If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
    default_file="/etc/audit/rules.d/$KEY.rules"
    # As other_filters may include paths, lets use a different delimiter for it
    # The "F" script expression tells sed to print the filenames where the expressions matched
    readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
    # Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
    if [ ${#files_to_inspect[@]} -eq "0" ]
    then
        file_to_inspect="/etc/audit/rules.d/$KEY.rules"
        files_to_inspect=("$file_to_inspect")
        if [ ! -e "$file_to_inspect" ]
        then
            touch "$file_to_inspect"
            chmod 0640 "$file_to_inspect"
        fi
    fi

    # After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
    skip=1

    for audit_file in "${files_to_inspect[@]}"
    do
        # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
        # i.e, collect rules that match:
        # * the action, list and arch, (2-nd argument)
        # * the other filters, (3-rd argument)
        # * the auid filters, (4-rd argument)
        readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

        candidate_rules=()
        # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
        for s_rule in "${similar_rules[@]}"
        do
            # Strip all the options and fields we know of,
            # than check if there was any field left over
            extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
            grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
        done

        if [[ ${#syscall_a[@]} -ge 1 ]]
        then
            # Check if the syscall we want is present in any of the similar existing rules
            for rule in "${candidate_rules[@]}"
            do
                rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
                all_syscalls_found=0
                for syscall in "${syscall_a[@]}"
                do
                    grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                       # A syscall was not found in the candidate rule
                       all_syscalls_found=1
                       }
                done
                if [[ $all_syscalls_found -eq 0 ]]
                then
                    # We found a rule with all the syscall(s) we want; skip rest of macro
                    skip=0
                    break
                fi

                # Check if this rule can be grouped with our target syscall and keep track of it
                for syscall_g in "${syscall_grouping[@]}"
                do
                    if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                    then
                        file_to_edit=${audit_file}
                        rule_to_edit=${rule}
                        rule_syscalls_to_edit=${rule_syscalls}
                    fi
                done
            done
        else
            # If there is any candidate rule, it is compliant; skip rest of macro
            if [ "${#candidate_rules[@]}" -gt 0 ]
            then
                skip=0
            fi
        fi

        if [ "$skip" -eq 0 ]; then
            break
        fi
    done

    if [ "$skip" -ne 0 ]; then
        # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
        # At this point we know if we need to either append the $full_rule or group
        # the syscall together with an exsiting rule

        # Append the full_rule if it cannot be grouped to any other rule
        if [ -z ${rule_to_edit+x} ]
        then
            # Build full_rule while avoid adding double spaces when other_filters is empty
            if [ "${#syscall_a[@]}" -gt 0 ]
            then
                syscall_string=""
                for syscall in "${syscall_a[@]}"
                do
                    syscall_string+=" -S $syscall"
                done
            fi
            other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
            auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
            full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
            echo "$full_rule" >> "$default_file"
            chmod o-rwx ${default_file}
        else
            # Check if the syscalls are declared as a comma separated list or
            # as multiple -S parameters
            if grep -q -- "," <<< "${rule_syscalls_to_edit}"
            then
                delimiter=","
            else
                delimiter=" -S "
            fi
            new_grouped_syscalls="${rule_syscalls_to_edit}"
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
                   # A syscall was not found in the candidate rule
                   new_grouped_syscalls+="${delimiter}${syscall}"
                   }
            done

            # Group the syscall in the rule
            sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
        fi
    fi
    unset syscall_a
    unset syscall_grouping
    unset syscall_string
    unset syscall
    unset file_to_edit
    unset rule_to_edit
    unset rule_syscalls_to_edit
    unset other_string
    unset auid_string
    unset full_rule

    # Load macro arguments into arrays
    read -a syscall_a <<< $SYSCALL
    read -a syscall_grouping <<< $SYSCALL_GROUPING

    # Create a list of audit *.rules files that should be inspected for presence and correctness
    # of a particular audit rule. The scheme is as follows:
    #
    # -----------------------------------------------------------------------------------------
    #  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
    # -----------------------------------------------------------------------------------------
    #        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
    # -----------------------------------------------------------------------------------------
    #        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
    #        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
    # -----------------------------------------------------------------------------------------
    #
    files_to_inspect=()


    # If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
    # file to the list of files to be inspected
    default_file="/etc/audit/audit.rules"
    files_to_inspect+=('/etc/audit/audit.rules' )

    # After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
    skip=1

    for audit_file in "${files_to_inspect[@]}"
    do
        # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
        # i.e, collect rules that match:
        # * the action, list and arch, (2-nd argument)
        # * the other filters, (3-rd argument)
        # * the auid filters, (4-rd argument)
        readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

        candidate_rules=()
        # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
        for s_rule in "${similar_rules[@]}"
        do
            # Strip all the options and fields we know of,
            # than check if there was any field left over
            extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
            grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
        done

        if [[ ${#syscall_a[@]} -ge 1 ]]
        then
            # Check if the syscall we want is present in any of the similar existing rules
            for rule in "${candidate_rules[@]}"
            do
                rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
                all_syscalls_found=0
                for syscall in "${syscall_a[@]}"
                do
                    grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                       # A syscall was not found in the candidate rule
                       all_syscalls_found=1
                       }
                done
                if [[ $all_syscalls_found -eq 0 ]]
                then
                    # We found a rule with all the syscall(s) we want; skip rest of macro
                    skip=0
                    break
                fi

                # Check if this rule can be grouped with our target syscall and keep track of it
                for syscall_g in "${syscall_grouping[@]}"
                do
                    if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                    then
                        file_to_edit=${audit_file}
                        rule_to_edit=${rule}
                        rule_syscalls_to_edit=${rule_syscalls}
                    fi
                done
            done
        else
            # If there is any candidate rule, it is compliant; skip rest of macro
            if [ "${#candidate_rules[@]}" -gt 0 ]
            then
                skip=0
            fi
        fi

        if [ "$skip" -eq 0 ]; then
            break
        fi
    done

    if [ "$skip" -ne 0 ]; then
        # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
        # At this point we know if we need to either append the $full_rule or group
        # the syscall together with an exsiting rule

        # Append the full_rule if it cannot be grouped to any other rule
        if [ -z ${rule_to_edit+x} ]
        then
            # Build full_rule while avoid adding double spaces when other_filters is empty
            if [ "${#syscall_a[@]}" -gt 0 ]
            then
                syscall_string=""
                for syscall in "${syscall_a[@]}"
                do
                    syscall_string+=" -S $syscall"
                done
            fi
            other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
            auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
            full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
            echo "$full_rule" >> "$default_file"
            chmod o-rwx ${default_file}
        else
            # Check if the syscalls are declared as a comma separated list or
            # as multiple -S parameters
            if grep -q -- "," <<< "${rule_syscalls_to_edit}"
            then
                delimiter=","
            else
                delimiter=" -S "
            fi
            new_grouped_syscalls="${rule_syscalls_to_edit}"
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
                   # A syscall was not found in the candidate rule
                   new_grouped_syscalls+="${delimiter}${syscall}"
                   }
            done

            # Group the syscall in the rule
            sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
        fi
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -a%20always%2Cexit%20-F%20arch%3Db64%20-S%20adjtimex%20-k%20audit_time_rules%0A-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20adjtimex%20-k%20audit_time_rules%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-syscall-adjtimex.rules
        overwrite: true

Rule   Record Attempts to Alter Time Through clock_settime   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S clock_settime -F a0=0x0 -F key=time-change
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S clock_settime -F a0=0x0 -F key=time-change
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S clock_settime -F a0=0x0 -F key=time-change
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S clock_settime -F a0=0x0 -F key=time-change
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined syscalls: 
-a always,exit -F arch=b64 -S adjtimex,settimeofday -F key=audit_time_rules
Rationale:
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_time_clock_settime
Identifiers:

CCE-27219-5

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-001487, CCI-000169
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.4.2.b
anssiR73
cis5.2.3.4
pcidss410.6.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27219-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_clock_settime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set architecture for audit tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27219-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_clock_settime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for clock_settime for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - clock_settime
      syscall_grouping: []

  - name: Check existence of clock_settime in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F a0=0x0 (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/time-change.rules
    set_fact: audit_file="/etc/audit/rules.d/time-change.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a0=0x0 (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a0=0x0 -F
        key=time-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - clock_settime
      syscall_grouping: []

  - name: Check existence of clock_settime in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F a0=0x0 (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F a0=0x0 (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F a0=0x0 -F
        key=time-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27219-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_clock_settime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for clock_settime for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - clock_settime
      syscall_grouping: []

  - name: Check existence of clock_settime in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F a0=0x0 (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/time-change.rules
    set_fact: audit_file="/etc/audit/rules.d/time-change.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F a0=0x0 (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a0=0x0 -F
        key=time-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - clock_settime
      syscall_grouping: []

  - name: Check existence of clock_settime in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F a0=0x0 (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F a0=0x0 (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F a0=0x0 -F
        key=time-change
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27219-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_clock_settime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS="-F a0=0x0"
	AUID_FILTERS=""
	SYSCALL="clock_settime"
	KEY="time-change"
	SYSCALL_GROUPING=""
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -a%20always%2Cexit%20-F%20arch%3Db64%20-S%20clock_settime%20-F%20a0%3D0x0%20-k%20time-change%0A-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20clock_settime%20-F%20a0%3D0x0%20-k%20time-change%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-syscall-clock-settime.rules
        overwrite: true

Rule   Record attempts to alter time through settimeofday   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-a always,exit -F arch=b32 -S settimeofday -F key=audit_time_rules
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S settimeofday -F key=audit_time_rules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-a always,exit -F arch=b32 -S settimeofday -F key=audit_time_rules
If the system is 64 bit then also add the following line: 
-a always,exit -F arch=b64 -S settimeofday -F key=audit_time_rules
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined syscalls: 
-a always,exit -F arch=b64 -S adjtimex,settimeofday -F key=audit_time_rules
Rationale:
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_time_settimeofday
Identifiers:

CCE-27216-1

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-001487, CCI-000169
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.4.2.b
cis5.2.3.4
pcidss410.6.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27216-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_settimeofday
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set architecture for audit tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27216-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_settimeofday
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for settimeofday for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - settimeofday
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of settimeofday in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_time_rules.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_time_rules.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - settimeofday
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of settimeofday in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27216-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_settimeofday
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for settimeofday for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - settimeofday
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of settimeofday in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_time_rules.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_time_rules.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - settimeofday
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of settimeofday in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27216-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_settimeofday
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
    # Create expected audit group and audit rule form for particular system call & architecture
    if [ ${ARCH} = "b32" ]
    then
        ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
        # stime system call is known at 32-bit arch (see e.g "$ ausyscall i386 stime" 's output)
        # so append it to the list of time group system calls to be audited
        SYSCALL="adjtimex settimeofday stime"
        SYSCALL_GROUPING="adjtimex settimeofday stime"
    elif [ ${ARCH} = "b64" ]
    then
        ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
        # stime system call isn't known at 64-bit arch (see "$ ausyscall x86_64 stime" 's output)
        # therefore don't add it to the list of time group system calls to be audited
        SYSCALL="adjtimex settimeofday"
        SYSCALL_GROUPING="adjtimex settimeofday"
    fi
    OTHER_FILTERS=""
    AUID_FILTERS=""
    KEY="audit_time_rules"
    # Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
    unset syscall_a
    unset syscall_grouping
    unset syscall_string
    unset syscall
    unset file_to_edit
    unset rule_to_edit
    unset rule_syscalls_to_edit
    unset other_string
    unset auid_string
    unset full_rule

    # Load macro arguments into arrays
    read -a syscall_a <<< $SYSCALL
    read -a syscall_grouping <<< $SYSCALL_GROUPING

    # Create a list of audit *.rules files that should be inspected for presence and correctness
    # of a particular audit rule. The scheme is as follows:
    #
    # -----------------------------------------------------------------------------------------
    #  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
    # -----------------------------------------------------------------------------------------
    #        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
    # -----------------------------------------------------------------------------------------
    #        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
    #        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
    # -----------------------------------------------------------------------------------------
    #
    files_to_inspect=()

    # If audit tool is 'augenrules', then check if the audit rule is defined
    # If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
    # If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
    default_file="/etc/audit/rules.d/$KEY.rules"
    # As other_filters may include paths, lets use a different delimiter for it
    # The "F" script expression tells sed to print the filenames where the expressions matched
    readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
    # Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
    if [ ${#files_to_inspect[@]} -eq "0" ]
    then
        file_to_inspect="/etc/audit/rules.d/$KEY.rules"
        files_to_inspect=("$file_to_inspect")
        if [ ! -e "$file_to_inspect" ]
        then
            touch "$file_to_inspect"
            chmod 0640 "$file_to_inspect"
        fi
    fi

    # After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
    skip=1

    for audit_file in "${files_to_inspect[@]}"
    do
        # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
        # i.e, collect rules that match:
        # * the action, list and arch, (2-nd argument)
        # * the other filters, (3-rd argument)
        # * the auid filters, (4-rd argument)
        readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

        candidate_rules=()
        # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
        for s_rule in "${similar_rules[@]}"
        do
            # Strip all the options and fields we know of,
            # than check if there was any field left over
            extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
            grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
        done

        if [[ ${#syscall_a[@]} -ge 1 ]]
        then
            # Check if the syscall we want is present in any of the similar existing rules
            for rule in "${candidate_rules[@]}"
            do
                rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
                all_syscalls_found=0
                for syscall in "${syscall_a[@]}"
                do
                    grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                       # A syscall was not found in the candidate rule
                       all_syscalls_found=1
                       }
                done
                if [[ $all_syscalls_found -eq 0 ]]
                then
                    # We found a rule with all the syscall(s) we want; skip rest of macro
                    skip=0
                    break
                fi

                # Check if this rule can be grouped with our target syscall and keep track of it
                for syscall_g in "${syscall_grouping[@]}"
                do
                    if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                    then
                        file_to_edit=${audit_file}
                        rule_to_edit=${rule}
                        rule_syscalls_to_edit=${rule_syscalls}
                    fi
                done
            done
        else
            # If there is any candidate rule, it is compliant; skip rest of macro
            if [ "${#candidate_rules[@]}" -gt 0 ]
            then
                skip=0
            fi
        fi

        if [ "$skip" -eq 0 ]; then
            break
        fi
    done

    if [ "$skip" -ne 0 ]; then
        # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
        # At this point we know if we need to either append the $full_rule or group
        # the syscall together with an exsiting rule

        # Append the full_rule if it cannot be grouped to any other rule
        if [ -z ${rule_to_edit+x} ]
        then
            # Build full_rule while avoid adding double spaces when other_filters is empty
            if [ "${#syscall_a[@]}" -gt 0 ]
            then
                syscall_string=""
                for syscall in "${syscall_a[@]}"
                do
                    syscall_string+=" -S $syscall"
                done
            fi
            other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
            auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
            full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
            echo "$full_rule" >> "$default_file"
            chmod o-rwx ${default_file}
        else
            # Check if the syscalls are declared as a comma separated list or
            # as multiple -S parameters
            if grep -q -- "," <<< "${rule_syscalls_to_edit}"
            then
                delimiter=","
            else
                delimiter=" -S "
            fi
            new_grouped_syscalls="${rule_syscalls_to_edit}"
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
                   # A syscall was not found in the candidate rule
                   new_grouped_syscalls+="${delimiter}${syscall}"
                   }
            done

            # Group the syscall in the rule
            sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
        fi
    fi
    unset syscall_a
    unset syscall_grouping
    unset syscall_string
    unset syscall
    unset file_to_edit
    unset rule_to_edit
    unset rule_syscalls_to_edit
    unset other_string
    unset auid_string
    unset full_rule

    # Load macro arguments into arrays
    read -a syscall_a <<< $SYSCALL
    read -a syscall_grouping <<< $SYSCALL_GROUPING

    # Create a list of audit *.rules files that should be inspected for presence and correctness
    # of a particular audit rule. The scheme is as follows:
    #
    # -----------------------------------------------------------------------------------------
    #  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
    # -----------------------------------------------------------------------------------------
    #        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
    # -----------------------------------------------------------------------------------------
    #        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
    #        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
    # -----------------------------------------------------------------------------------------
    #
    files_to_inspect=()


    # If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
    # file to the list of files to be inspected
    default_file="/etc/audit/audit.rules"
    files_to_inspect+=('/etc/audit/audit.rules' )

    # After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
    skip=1

    for audit_file in "${files_to_inspect[@]}"
    do
        # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
        # i.e, collect rules that match:
        # * the action, list and arch, (2-nd argument)
        # * the other filters, (3-rd argument)
        # * the auid filters, (4-rd argument)
        readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

        candidate_rules=()
        # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
        for s_rule in "${similar_rules[@]}"
        do
            # Strip all the options and fields we know of,
            # than check if there was any field left over
            extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
            grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
        done

        if [[ ${#syscall_a[@]} -ge 1 ]]
        then
            # Check if the syscall we want is present in any of the similar existing rules
            for rule in "${candidate_rules[@]}"
            do
                rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
                all_syscalls_found=0
                for syscall in "${syscall_a[@]}"
                do
                    grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                       # A syscall was not found in the candidate rule
                       all_syscalls_found=1
                       }
                done
                if [[ $all_syscalls_found -eq 0 ]]
                then
                    # We found a rule with all the syscall(s) we want; skip rest of macro
                    skip=0
                    break
                fi

                # Check if this rule can be grouped with our target syscall and keep track of it
                for syscall_g in "${syscall_grouping[@]}"
                do
                    if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                    then
                        file_to_edit=${audit_file}
                        rule_to_edit=${rule}
                        rule_syscalls_to_edit=${rule_syscalls}
                    fi
                done
            done
        else
            # If there is any candidate rule, it is compliant; skip rest of macro
            if [ "${#candidate_rules[@]}" -gt 0 ]
            then
                skip=0
            fi
        fi

        if [ "$skip" -eq 0 ]; then
            break
        fi
    done

    if [ "$skip" -ne 0 ]; then
        # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
        # At this point we know if we need to either append the $full_rule or group
        # the syscall together with an exsiting rule

        # Append the full_rule if it cannot be grouped to any other rule
        if [ -z ${rule_to_edit+x} ]
        then
            # Build full_rule while avoid adding double spaces when other_filters is empty
            if [ "${#syscall_a[@]}" -gt 0 ]
            then
                syscall_string=""
                for syscall in "${syscall_a[@]}"
                do
                    syscall_string+=" -S $syscall"
                done
            fi
            other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
            auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
            full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
            echo "$full_rule" >> "$default_file"
            chmod o-rwx ${default_file}
        else
            # Check if the syscalls are declared as a comma separated list or
            # as multiple -S parameters
            if grep -q -- "," <<< "${rule_syscalls_to_edit}"
            then
                delimiter=","
            else
                delimiter=" -S "
            fi
            new_grouped_syscalls="${rule_syscalls_to_edit}"
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
                   # A syscall was not found in the candidate rule
                   new_grouped_syscalls+="${delimiter}${syscall}"
                   }
            done

            # Group the syscall in the rule
            sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
        fi
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -a%20always%2Cexit%20-F%20arch%3Db64%20-S%20settimeofday%20-k%20audit_time_rules%0A-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20settimeofday%20-k%20audit_time_rules%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-syscall-settimeofday.rules
        overwrite: true

Rule   Record Attempts to Alter Time Through stime   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d for both 32 bit and 64 bit systems: 
-a always,exit -F arch=b32 -S stime -F key=audit_time_rules
Since the 64 bit version of the "stime" system call is not defined in the audit lookup table, the corresponding "-F arch=b64" form of this rule is not expected to be defined on 64 bit systems (the aforementioned "-F arch=b32" stime rule form itself is sufficient for both 32 bit and 64 bit systems). If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file for both 32 bit and 64 bit systems: 
-a always,exit -F arch=b32 -S stime -F key=audit_time_rules
Since the 64 bit version of the "stime" system call is not defined in the audit lookup table, the corresponding "-F arch=b64" form of this rule is not expected to be defined on 64 bit systems (the aforementioned "-F arch=b32" stime rule form itself is sufficient for both 32 bit and 64 bit systems). The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined system calls: 
-a always,exit -F arch=b64 -S adjtimex,settimeofday -F key=audit_time_rules
Rationale:
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_time_stime
Identifiers:

CCE-27299-7

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-001487, CCI-000169
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.4.2.b
anssiR73
cis5.2.3.4
pcidss410.6.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27299-7
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_stime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Perform remediation of Audit rules for stime syscall for x86 platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - stime
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of stime in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_time_rules.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_time_rules.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - stime
      syscall_grouping:
      - adjtimex
      - settimeofday
      - stime

  - name: Check existence of stime in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_time_rules
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ( not ( ansible_architecture == "aarch64" ) and not ( ansible_architecture ==
    "s390x" ) )
  tags:
  - CCE-27299-7
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_stime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit && { ( ! ( grep -q aarch64 /proc/sys/kernel/osrelease ) && ! ( grep -q s390x /proc/sys/kernel/osrelease ) ); }; then

# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
    # Create expected audit group and audit rule form for particular system call & architecture
    if [ ${ARCH} = "b32" ]
    then
        ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
        # stime system call is known at 32-bit arch (see e.g "$ ausyscall i386 stime" 's output)
        # so append it to the list of time group system calls to be audited
        SYSCALL="adjtimex settimeofday stime"
        SYSCALL_GROUPING="adjtimex settimeofday stime"
    elif [ ${ARCH} = "b64" ]
    then
        ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
        # stime system call isn't known at 64-bit arch (see "$ ausyscall x86_64 stime" 's output)
        # therefore don't add it to the list of time group system calls to be audited
        SYSCALL="adjtimex settimeofday"
        SYSCALL_GROUPING="adjtimex settimeofday"
    fi
    OTHER_FILTERS=""
    AUID_FILTERS=""
    KEY="audit_time_rules"
    # Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
    unset syscall_a
    unset syscall_grouping
    unset syscall_string
    unset syscall
    unset file_to_edit
    unset rule_to_edit
    unset rule_syscalls_to_edit
    unset other_string
    unset auid_string
    unset full_rule

    # Load macro arguments into arrays
    read -a syscall_a <<< $SYSCALL
    read -a syscall_grouping <<< $SYSCALL_GROUPING

    # Create a list of audit *.rules files that should be inspected for presence and correctness
    # of a particular audit rule. The scheme is as follows:
    #
    # -----------------------------------------------------------------------------------------
    #  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
    # -----------------------------------------------------------------------------------------
    #        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
    # -----------------------------------------------------------------------------------------
    #        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
    #        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
    # -----------------------------------------------------------------------------------------
    #
    files_to_inspect=()

    # If audit tool is 'augenrules', then check if the audit rule is defined
    # If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
    # If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
    default_file="/etc/audit/rules.d/$KEY.rules"
    # As other_filters may include paths, lets use a different delimiter for it
    # The "F" script expression tells sed to print the filenames where the expressions matched
    readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
    # Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
    if [ ${#files_to_inspect[@]} -eq "0" ]
    then
        file_to_inspect="/etc/audit/rules.d/$KEY.rules"
        files_to_inspect=("$file_to_inspect")
        if [ ! -e "$file_to_inspect" ]
        then
            touch "$file_to_inspect"
            chmod 0640 "$file_to_inspect"
        fi
    fi

    # After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
    skip=1

    for audit_file in "${files_to_inspect[@]}"
    do
        # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
        # i.e, collect rules that match:
        # * the action, list and arch, (2-nd argument)
        # * the other filters, (3-rd argument)
        # * the auid filters, (4-rd argument)
        readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

        candidate_rules=()
        # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
        for s_rule in "${similar_rules[@]}"
        do
            # Strip all the options and fields we know of,
            # than check if there was any field left over
            extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
            grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
        done

        if [[ ${#syscall_a[@]} -ge 1 ]]
        then
            # Check if the syscall we want is present in any of the similar existing rules
            for rule in "${candidate_rules[@]}"
            do
                rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
                all_syscalls_found=0
                for syscall in "${syscall_a[@]}"
                do
                    grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                       # A syscall was not found in the candidate rule
                       all_syscalls_found=1
                       }
                done
                if [[ $all_syscalls_found -eq 0 ]]
                then
                    # We found a rule with all the syscall(s) we want; skip rest of macro
                    skip=0
                    break
                fi

                # Check if this rule can be grouped with our target syscall and keep track of it
                for syscall_g in "${syscall_grouping[@]}"
                do
                    if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                    then
                        file_to_edit=${audit_file}
                        rule_to_edit=${rule}
                        rule_syscalls_to_edit=${rule_syscalls}
                    fi
                done
            done
        else
            # If there is any candidate rule, it is compliant; skip rest of macro
            if [ "${#candidate_rules[@]}" -gt 0 ]
            then
                skip=0
            fi
        fi

        if [ "$skip" -eq 0 ]; then
            break
        fi
    done

    if [ "$skip" -ne 0 ]; then
        # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
        # At this point we know if we need to either append the $full_rule or group
        # the syscall together with an exsiting rule

        # Append the full_rule if it cannot be grouped to any other rule
        if [ -z ${rule_to_edit+x} ]
        then
            # Build full_rule while avoid adding double spaces when other_filters is empty
            if [ "${#syscall_a[@]}" -gt 0 ]
            then
                syscall_string=""
                for syscall in "${syscall_a[@]}"
                do
                    syscall_string+=" -S $syscall"
                done
            fi
            other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
            auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
            full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
            echo "$full_rule" >> "$default_file"
            chmod o-rwx ${default_file}
        else
            # Check if the syscalls are declared as a comma separated list or
            # as multiple -S parameters
            if grep -q -- "," <<< "${rule_syscalls_to_edit}"
            then
                delimiter=","
            else
                delimiter=" -S "
            fi
            new_grouped_syscalls="${rule_syscalls_to_edit}"
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
                   # A syscall was not found in the candidate rule
                   new_grouped_syscalls+="${delimiter}${syscall}"
                   }
            done

            # Group the syscall in the rule
            sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
        fi
    fi
    unset syscall_a
    unset syscall_grouping
    unset syscall_string
    unset syscall
    unset file_to_edit
    unset rule_to_edit
    unset rule_syscalls_to_edit
    unset other_string
    unset auid_string
    unset full_rule

    # Load macro arguments into arrays
    read -a syscall_a <<< $SYSCALL
    read -a syscall_grouping <<< $SYSCALL_GROUPING

    # Create a list of audit *.rules files that should be inspected for presence and correctness
    # of a particular audit rule. The scheme is as follows:
    #
    # -----------------------------------------------------------------------------------------
    #  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
    # -----------------------------------------------------------------------------------------
    #        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
    # -----------------------------------------------------------------------------------------
    #        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
    #        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
    # -----------------------------------------------------------------------------------------
    #
    files_to_inspect=()


    # If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
    # file to the list of files to be inspected
    default_file="/etc/audit/audit.rules"
    files_to_inspect+=('/etc/audit/audit.rules' )

    # After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
    skip=1

    for audit_file in "${files_to_inspect[@]}"
    do
        # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
        # i.e, collect rules that match:
        # * the action, list and arch, (2-nd argument)
        # * the other filters, (3-rd argument)
        # * the auid filters, (4-rd argument)
        readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

        candidate_rules=()
        # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
        for s_rule in "${similar_rules[@]}"
        do
            # Strip all the options and fields we know of,
            # than check if there was any field left over
            extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
            grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
        done

        if [[ ${#syscall_a[@]} -ge 1 ]]
        then
            # Check if the syscall we want is present in any of the similar existing rules
            for rule in "${candidate_rules[@]}"
            do
                rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
                all_syscalls_found=0
                for syscall in "${syscall_a[@]}"
                do
                    grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                       # A syscall was not found in the candidate rule
                       all_syscalls_found=1
                       }
                done
                if [[ $all_syscalls_found -eq 0 ]]
                then
                    # We found a rule with all the syscall(s) we want; skip rest of macro
                    skip=0
                    break
                fi

                # Check if this rule can be grouped with our target syscall and keep track of it
                for syscall_g in "${syscall_grouping[@]}"
                do
                    if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                    then
                        file_to_edit=${audit_file}
                        rule_to_edit=${rule}
                        rule_syscalls_to_edit=${rule_syscalls}
                    fi
                done
            done
        else
            # If there is any candidate rule, it is compliant; skip rest of macro
            if [ "${#candidate_rules[@]}" -gt 0 ]
            then
                skip=0
            fi
        fi

        if [ "$skip" -eq 0 ]; then
            break
        fi
    done

    if [ "$skip" -ne 0 ]; then
        # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
        # At this point we know if we need to either append the $full_rule or group
        # the syscall together with an exsiting rule

        # Append the full_rule if it cannot be grouped to any other rule
        if [ -z ${rule_to_edit+x} ]
        then
            # Build full_rule while avoid adding double spaces when other_filters is empty
            if [ "${#syscall_a[@]}" -gt 0 ]
            then
                syscall_string=""
                for syscall in "${syscall_a[@]}"
                do
                    syscall_string+=" -S $syscall"
                done
            fi
            other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
            auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
            full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
            echo "$full_rule" >> "$default_file"
            chmod o-rwx ${default_file}
        else
            # Check if the syscalls are declared as a comma separated list or
            # as multiple -S parameters
            if grep -q -- "," <<< "${rule_syscalls_to_edit}"
            then
                delimiter=","
            else
                delimiter=" -S "
            fi
            new_grouped_syscalls="${rule_syscalls_to_edit}"
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
                   # A syscall was not found in the candidate rule
                   new_grouped_syscalls+="${delimiter}${syscall}"
                   }
            done

            # Group the syscall in the rule
            sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
        fi
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -a%20always%2Cexit%20-F%20arch%3Db64%20-S%20stime%20-k%20audit_time_rules%0A-a%20always%2Cexit%20-F%20arch%3Db32%20-S%20stime%20-k%20audit_time_rules%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-syscall-stime.rules
        overwrite: true

Rule   Record Attempts to Alter the localtime File   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-w /etc/localtime -p wa -k audit_time_rules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-w /etc/localtime -p wa -k audit_time_rules
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport and should always be used.
Rationale:
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_time_watch_localtime
Identifiers:

CCE-27310-2

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-001487, CCI-000169
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.4.2.b
anssiR73
cis5.2.3.4
pcidss410.6.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/localtime already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/localtime\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_time_rules
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_time_rules$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_time_rules.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_time_rules.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/localtime in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/localtime -p wa -k audit_time_rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/localtime already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/localtime\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/localtime in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/localtime -p wa -k audit_time_rules
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27310-2
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.2.b
  - PCI-DSSv4-10.6.3
  - audit_rules_time_watch_localtime
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/localtime" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/localtime $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/localtime$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/localtime -p wa -k audit_time_rules" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_time_rules.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/localtime" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_time_rules.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_time_rules.rules"
    # If the audit_time_rules.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/localtime" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/localtime $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/localtime$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/localtime -p wa -k audit_time_rules" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -w%20/etc/localtime%20-p%20wa%20-k%20audit_time_rules%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-etclocaltime-wa-audit_time_rules.rules
        overwrite: true

Rule   Make the auditd Configuration Immutable   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d in order to make the auditd configuration immutable: 
-e 2
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file in order to make the auditd configuration immutable: 
-e 2
With this setting, a reboot will be required to change any audit rules.
Rationale:
Making the audit configuration immutable prevents accidental as well as malicious modification of the audit rules, although it may be problematic if legitimate changes are needed during system operation.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_immutable
Identifiers:

CCE-27097-5

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 3, 4, 5, 6, 7, 8
cjis5.4.1.1
cobit5APO01.06, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, BAI03.05, BAI08.02, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS05.04, DSS05.07, DSS06.02, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.3.1, 3.4.3
disaCCI-000162, CCI-000163, CCI-000164
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.310(a)(2)(iv), 164.312(d), 164.310(d)(2)(iii), 164.312(b), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.7.3, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 5.2, SR 6.1
iso27001-2013A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistAC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, ID.SC-4, PR.AC-4, PR.DS-5, PR.PT-1, RS.AN-1, RS.AN-4
pcidssReq-10.5.2
os-srgSRG-OS-000057-GPOS-00027, SRG-OS-000058-GPOS-00028, SRG-OS-000059-GPOS-00029
app-srg-ctrSRG-APP-000119-CTR-000245, SRG-APP-000120-CTR-000250
anssiR73
cis5.2.3.20
pcidss410.3.2

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27097-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-171-3.4.3
  - NIST-800-53-AC-6(9)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3.2
  - audit_rules_immutable
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Collect all files from /etc/audit/rules.d with .rules extension
  find:
    paths: /etc/audit/rules.d/
    patterns: '*.rules'
  register: find_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27097-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-171-3.4.3
  - NIST-800-53-AC-6(9)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3.2
  - audit_rules_immutable
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Remove the -e option from all Audit config files
  lineinfile:
    path: '{{ item }}'
    regexp: ^\s*(?:-e)\s+.*$
    state: absent
  loop: '{{ find_rules_d.files | map(attribute=''path'') | list + [''/etc/audit/audit.rules'']
    }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27097-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-171-3.4.3
  - NIST-800-53-AC-6(9)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3.2
  - audit_rules_immutable
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add Audit -e option into /etc/audit/rules.d/immutable.rules and /etc/audit/audit.rules
  lineinfile:
    path: '{{ item }}'
    create: true
    line: -e 2
    mode: o-rwx
  loop:
  - /etc/audit/audit.rules
  - /etc/audit/rules.d/immutable.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27097-5
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-171-3.4.3
  - NIST-800-53-AC-6(9)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3.2
  - audit_rules_immutable
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Traverse all of:
#
# /etc/audit/audit.rules,			(for auditctl case)
# /etc/audit/rules.d/*.rules			(for augenrules case)
#
# files to check if '-e .*' setting is present in that '*.rules' file already.
# If found, delete such occurrence since auditctl(8) manual page instructs the
# '-e 2' rule should be placed as the last rule in the configuration
find /etc/audit /etc/audit/rules.d -maxdepth 1 -type f -name '*.rules' -exec sed -i '/-e[[:space:]]\+.*/d' {} ';'

# Append '-e 2' requirement at the end of both:
# * /etc/audit/audit.rules file 		(for auditctl case)
# * /etc/audit/rules.d/immutable.rules		(for augenrules case)

for AUDIT_FILE in "/etc/audit/audit.rules" "/etc/audit/rules.d/immutable.rules"
do
	echo '' >> $AUDIT_FILE
	echo '# Set the audit.rules configuration immutable per security requirements' >> $AUDIT_FILE
	echo '# Reboot is required to change audit rules once this setting is applied' >> $AUDIT_FILE
	echo '-e 2' >> $AUDIT_FILE
	chmod o-rwx $AUDIT_FILE
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,-e%202%0A
        mode: 0600
        path: /etc/audit/rules.d/90-immutable.rules
        overwrite: true

Rule   Record Events that Modify the System's Mandatory Access Controls   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-w /etc/selinux/ -p wa -k MAC-policy
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-w /etc/selinux/ -p wa -k MAC-policy
Rationale:
The system's mandatory access policy (SELinux) should not be arbitrarily changed by anything other than administrator action. All changes to MAC policy should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_mac_modification
Identifiers:

CCE-27168-4

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.8
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.5
anssiR73
cis5.2.3.14
pcidss410.3.4

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/selinux/ already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/selinux/\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key MAC-policy
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)MAC-policy$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/MAC-policy.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/MAC-policy.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/selinux/ in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/selinux/ -p wa -k MAC-policy
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/selinux/ already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/selinux/\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/selinux/ in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/selinux/ -p wa -k MAC-policy
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27168-4
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.8
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_mac_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/selinux/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/selinux/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/selinux/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/selinux/ -p wa -k MAC-policy" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/MAC-policy.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/selinux/" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/MAC-policy.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/MAC-policy.rules"
    # If the MAC-policy.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/selinux/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/selinux/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/selinux/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/selinux/ -p wa -k MAC-policy" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -w%20/etc/selinux/%20-p%20wa%20-k%20MAC-policy%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-etcselinux-wa-MAC-policy.rules
        overwrite: true

Rule   Ensure auditd Collects Information on Exporting to Media (successful)   [ref]

At a minimum, the audit system should collect media exportation events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S mount -F auid>=1000 -F auid!=unset -F key=export
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S mount -F auid>=1000 -F auid!=unset -F key=export
Rationale:
The unauthorized exportation of data to external media could result in an information leak where classified information, Privacy Act information, and intellectual property could be lost. An audit trail should be created each time a filesystem is mounted to help identify and guard against information loss.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_media_export
Identifiers:

CCE-27447-2

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.2.7
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215
app-srg-ctrSRG-APP-000495-CTR-001235
stigidRHEL-07-030740
anssiR73
cis5.2.3.10
pcidss410.2.1.7
stigrefSV-204552r861053_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27447-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030740
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_media_export
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Set architecture for audit mount tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27447-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030740
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_media_export
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for mount for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - mount
      syscall_grouping: []

  - name: Check existence of mount in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - mount
      syscall_grouping: []

  - name: Check existence of mount in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27447-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030740
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_media_export
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Perform remediation of Audit rules for mount for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - mount
      syscall_grouping: []

  - name: Check existence of mount in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/perm_mod.rules
    set_fact: audit_file="/etc/audit/rules.d/perm_mod.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k
        |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - mount
      syscall_grouping: []

  - name: Check existence of mount in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* -F auid>=1000 -F auid!=unset (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( -F auid>=1000 -F auid!=unset (?:-k |-F
        key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F auid>=1000
        -F auid!=unset -F key=perm_mod
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27447-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030740
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.7
  - PCI-DSSv4-10.2.1.7
  - audit_rules_media_export
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS="-F auid>=1000 -F auid!=unset"
	SYSCALL="mount"
	KEY="perm_mod"
	SYSCALL_GROUPING=""

	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify the System's Network Environment   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S sethostname,setdomainname -F key=audit_rules_networkconfig_modification
-w /etc/issue -p wa -k audit_rules_networkconfig_modification
-w /etc/issue.net -p wa -k audit_rules_networkconfig_modification
-w /etc/hosts -p wa -k audit_rules_networkconfig_modification
-w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system: 
-a always,exit -F arch=ARCH -S sethostname,setdomainname -F key=audit_rules_networkconfig_modification
-w /etc/issue -p wa -k audit_rules_networkconfig_modification
-w /etc/issue.net -p wa -k audit_rules_networkconfig_modification
-w /etc/hosts -p wa -k audit_rules_networkconfig_modification
-w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification
Rationale:
The network environment should not be modified by anything other than administrator action. Any change to network parameters should be audited.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_networkconfig_modification
Identifiers:

CCE-27076-9

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
pcidssReq-10.5.5
anssiR73
cis5.2.3.5
pcidss410.3.4

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set architecture for audit tasks
  set_fact:
    audit_arch: b64
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_architecture == "aarch64" or ansible_architecture == "ppc64" or ansible_architecture
    == "ppc64le" or ansible_architecture == "s390x" or ansible_architecture == "x86_64"
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Remediate audit rules for network configuration for 32bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - sethostname
      - setdomainname
      syscall_grouping:
      - sethostname
      - setdomainname

  - name: Check existence of sethostname, setdomainname in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_rules_networkconfig_modification.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_rules_networkconfig_modification.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_rules_networkconfig_modification
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - sethostname
      - setdomainname
      syscall_grouping:
      - sethostname
      - setdomainname

  - name: Check existence of sethostname, setdomainname in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b32(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b32)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b32 -S {{ syscalls | join(',') }} -F key=audit_rules_networkconfig_modification
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Remediate audit rules for network configuration for 64bit platform
  block:

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - sethostname
      - setdomainname
      syscall_grouping:
      - sethostname
      - setdomainname

  - name: Check existence of sethostname, setdomainname in /etc/audit/rules.d/
    find:
      paths: /etc/audit/rules.d
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: '*.rules'
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Reset syscalls found per file
    set_fact:
      syscalls_per_file: {}
      found_paths_dict: {}

  - name: Declare syscalls found per file
    set_fact: syscalls_per_file="{{ syscalls_per_file | combine( {item.files[0].path
      :[item.item] + syscalls_per_file.get(item.files[0].path, []) } ) }}"
    loop: '{{ find_command.results | selectattr(''matched'') | list }}'

  - name: Declare files where syscalls were found
    set_fact: found_paths="{{ find_command.results | map(attribute='files') | flatten
      | map(attribute='path') | list }}"

  - name: Count occurrences of syscalls in paths
    set_fact: found_paths_dict="{{ found_paths_dict | combine({ item:1+found_paths_dict.get(item,
      0) }) }}"
    loop: '{{ find_command.results | map(attribute=''files'') | flatten | map(attribute=''path'')
      | list }}'

  - name: Get path with most syscalls
    set_fact: audit_file="{{ (found_paths_dict | dict2items() | sort(attribute='value')
      | last).key }}"
    when: found_paths | length >= 1

  - name: No file with syscall found, set path to /etc/audit/rules.d/audit_rules_networkconfig_modification.rules
    set_fact: audit_file="/etc/audit/rules.d/audit_rules_networkconfig_modification.rules"
    when: found_paths | length == 0

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_per_file[audit_file]
        | join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F key=audit_rules_networkconfig_modification
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0

  - name: Declare list of syscalls
    set_fact:
      syscalls:
      - sethostname
      - setdomainname
      syscall_grouping:
      - sethostname
      - setdomainname

  - name: Check existence of sethostname, setdomainname in /etc/audit/audit.rules
    find:
      paths: /etc/audit
      contains: -a always,exit -F arch=b64(( -S |,)\w+)*(( -S |,){{ item }})+(( -S
        |,)\w+)* (-k\s+|-F\s+key=)\S+\s*$
      patterns: audit.rules
    register: find_command
    loop: '{{ (syscall_grouping + syscalls) | unique }}'

  - name: Set path to /etc/audit/audit.rules
    set_fact: audit_file="/etc/audit/audit.rules"

  - name: Declare found syscalls
    set_fact: syscalls_found="{{ find_command.results | selectattr('matched') | map(attribute='item')
      | list }}"

  - name: Declare missing syscalls
    set_fact: missing_syscalls="{{ syscalls | difference(syscalls_found) }}"

  - name: Replace the audit rule in {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      regexp: (-a always,exit -F arch=b64)(?=.*(?:(?:-S |,)(?:{{ syscalls_found |
        join("|") }}))\b)((?:( -S |,)\w+)+)( (?:-k |-F key=)\w+)
      line: \1\2\3{{ missing_syscalls | join("\3") }}\4
      backrefs: true
      state: present
    when: syscalls_found | length > 0 and missing_syscalls | length > 0

  - name: Add the audit rule to {{ audit_file }}
    lineinfile:
      path: '{{ audit_file }}'
      line: -a always,exit -F arch=b64 -S {{ syscalls | join(',') }} -F key=audit_rules_networkconfig_modification
      create: true
      mode: o-rwx
      state: present
    when: syscalls_found | length == 0
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - audit_arch == "b64"
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/issue already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/issue\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_networkconfig_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_networkconfig_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_networkconfig_modification.rules as the
    recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_networkconfig_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/issue in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/issue -p wa -k audit_rules_networkconfig_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/issue already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/issue\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/issue in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/issue -p wa -k audit_rules_networkconfig_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/issue.net already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/issue.net\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_networkconfig_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_networkconfig_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_networkconfig_modification.rules as the
    recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_networkconfig_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/issue.net in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/issue.net -p wa -k audit_rules_networkconfig_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/issue.net already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/issue.net\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/issue.net in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/issue.net -p wa -k audit_rules_networkconfig_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/hosts already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/hosts\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_networkconfig_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_networkconfig_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_networkconfig_modification.rules as the
    recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_networkconfig_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/hosts in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/hosts -p wa -k audit_rules_networkconfig_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/hosts already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/hosts\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/hosts in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/hosts -p wa -k audit_rules_networkconfig_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/sysconfig/network already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/sysconfig/network\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_networkconfig_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_networkconfig_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_networkconfig_modification.rules as the
    recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_networkconfig_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/sysconfig/network in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/sysconfig/network already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/sysconfig/network\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/sysconfig/network in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27076-9
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.5
  - PCI-DSSv4-10.3.4
  - audit_rules_networkconfig_modification
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# First perform the remediation of the syscall rule
# Retrieve hardware architecture of the underlying system
[ "$(getconf LONG_BIT)" = "32" ] && RULE_ARCHS=("b32") || RULE_ARCHS=("b32" "b64")

for ARCH in "${RULE_ARCHS[@]}"
do
	ACTION_ARCH_FILTERS="-a always,exit -F arch=$ARCH"
	OTHER_FILTERS=""
	AUID_FILTERS=""
	SYSCALL="sethostname setdomainname"
	KEY="audit_rules_networkconfig_modification"
	SYSCALL_GROUPING="sethostname setdomainname"
	# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()

# If audit tool is 'augenrules', then check if the audit rule is defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to the list for inspection
# If rule isn't defined yet, add '/etc/audit/rules.d/$key.rules' to the list for inspection
default_file="/etc/audit/rules.d/$KEY.rules"
# As other_filters may include paths, lets use a different delimiter for it
# The "F" script expression tells sed to print the filenames where the expressions matched
readarray -t files_to_inspect < <(sed -s -n -e "/^$ACTION_ARCH_FILTERS/!d" -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" -e "F" /etc/audit/rules.d/*.rules)
# Case when particular rule isn't defined in /etc/audit/rules.d/*.rules yet
if [ ${#files_to_inspect[@]} -eq "0" ]
then
    file_to_inspect="/etc/audit/rules.d/$KEY.rules"
    files_to_inspect=("$file_to_inspect")
    if [ ! -e "$file_to_inspect" ]
    then
        touch "$file_to_inspect"
        chmod 0640 "$file_to_inspect"
    fi
fi

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
	unset syscall_a
unset syscall_grouping
unset syscall_string
unset syscall
unset file_to_edit
unset rule_to_edit
unset rule_syscalls_to_edit
unset other_string
unset auid_string
unset full_rule

# Load macro arguments into arrays
read -a syscall_a <<< $SYSCALL
read -a syscall_grouping <<< $SYSCALL_GROUPING

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
#  Tool used to load audit rules | Rule already defined  |  Audit rules file to inspect    |
# -----------------------------------------------------------------------------------------
#        auditctl                |     Doesn't matter    |  /etc/audit/audit.rules         |
# -----------------------------------------------------------------------------------------
#        augenrules              |          Yes          |  /etc/audit/rules.d/*.rules     |
#        augenrules              |          No           |  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
#
files_to_inspect=()


# If audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# file to the list of files to be inspected
default_file="/etc/audit/audit.rules"
files_to_inspect+=('/etc/audit/audit.rules' )

# After converting to jinja, we cannot return; therefore we skip the rest of the macro if needed instead
skip=1

for audit_file in "${files_to_inspect[@]}"
do
    # Filter existing $audit_file rules' definitions to select those that satisfy the rule pattern,
    # i.e, collect rules that match:
    # * the action, list and arch, (2-nd argument)
    # * the other filters, (3-rd argument)
    # * the auid filters, (4-rd argument)
    readarray -t similar_rules < <(sed -e "/^$ACTION_ARCH_FILTERS/!d"  -e "\#$OTHER_FILTERS#!d" -e "/$AUID_FILTERS/!d" "$audit_file")

    candidate_rules=()
    # Filter out rules that have more fields then required. This will remove rules more specific than the required scope
    for s_rule in "${similar_rules[@]}"
    do
        # Strip all the options and fields we know of,
        # than check if there was any field left over
        extra_fields=$(sed -E -e "s/^$ACTION_ARCH_FILTERS//"  -e "s#$OTHER_FILTERS##" -e "s/$AUID_FILTERS//" -e "s/((:?-S [[:alnum:],]+)+)//g" -e "s/-F key=\w+|-k \w+//"<<< "$s_rule")
        grep -q -- "-F" <<< "$extra_fields" || candidate_rules+=("$s_rule")
    done

    if [[ ${#syscall_a[@]} -ge 1 ]]
    then
        # Check if the syscall we want is present in any of the similar existing rules
        for rule in "${candidate_rules[@]}"
        do
            rule_syscalls=$(echo "$rule" | grep -o -P '(-S [\w,]+)+' | xargs)
            all_syscalls_found=0
            for syscall in "${syscall_a[@]}"
            do
                grep -q -- "\b${syscall}\b" <<< "$rule_syscalls" || {
                   # A syscall was not found in the candidate rule
                   all_syscalls_found=1
                   }
            done
            if [[ $all_syscalls_found -eq 0 ]]
            then
                # We found a rule with all the syscall(s) we want; skip rest of macro
                skip=0
                break
            fi

            # Check if this rule can be grouped with our target syscall and keep track of it
            for syscall_g in "${syscall_grouping[@]}"
            do
                if grep -q -- "\b${syscall_g}\b" <<< "$rule_syscalls"
                then
                    file_to_edit=${audit_file}
                    rule_to_edit=${rule}
                    rule_syscalls_to_edit=${rule_syscalls}
                fi
            done
        done
    else
        # If there is any candidate rule, it is compliant; skip rest of macro
        if [ "${#candidate_rules[@]}" -gt 0 ]
        then
            skip=0
        fi
    fi

    if [ "$skip" -eq 0 ]; then
        break
    fi
done

if [ "$skip" -ne 0 ]; then
    # We checked all rules that matched the expected resemblance pattern (action, arch & auid)
    # At this point we know if we need to either append the $full_rule or group
    # the syscall together with an exsiting rule

    # Append the full_rule if it cannot be grouped to any other rule
    if [ -z ${rule_to_edit+x} ]
    then
        # Build full_rule while avoid adding double spaces when other_filters is empty
        if [ "${#syscall_a[@]}" -gt 0 ]
        then
            syscall_string=""
            for syscall in "${syscall_a[@]}"
            do
                syscall_string+=" -S $syscall"
            done
        fi
        other_string=$([[ $OTHER_FILTERS ]] && echo " $OTHER_FILTERS") || /bin/true
        auid_string=$([[ $AUID_FILTERS ]] && echo " $AUID_FILTERS") || /bin/true
        full_rule="$ACTION_ARCH_FILTERS${syscall_string}${other_string}${auid_string} -F key=$KEY" || /bin/true
        echo "$full_rule" >> "$default_file"
        chmod o-rwx ${default_file}
    else
        # Check if the syscalls are declared as a comma separated list or
        # as multiple -S parameters
        if grep -q -- "," <<< "${rule_syscalls_to_edit}"
        then
            delimiter=","
        else
            delimiter=" -S "
        fi
        new_grouped_syscalls="${rule_syscalls_to_edit}"
        for syscall in "${syscall_a[@]}"
        do
            grep -q -- "\b${syscall}\b" <<< "${rule_syscalls_to_edit}" || {
               # A syscall was not found in the candidate rule
               new_grouped_syscalls+="${delimiter}${syscall}"
               }
        done

        # Group the syscall in the rule
        sed -i -e "\#${rule_to_edit}#s#${rule_syscalls_to_edit}#${new_grouped_syscalls}#" "$file_to_edit"
    fi
fi
done

# Then perform the remediations for the watch rules
# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/issue" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/issue $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/issue$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/issue -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/issue" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_networkconfig_modification.rules"
    # If the audit_rules_networkconfig_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/issue" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/issue $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/issue$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/issue -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/issue.net" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/issue.net $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/issue.net$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/issue.net -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/issue.net" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_networkconfig_modification.rules"
    # If the audit_rules_networkconfig_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/issue.net" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/issue.net $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/issue.net$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/issue.net -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/hosts" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/hosts $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/hosts$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/hosts -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/hosts" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_networkconfig_modification.rules"
    # If the audit_rules_networkconfig_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/hosts" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/hosts $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/hosts$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/hosts -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/sysconfig/network" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sysconfig/network $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sysconfig/network$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/sysconfig/network" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_networkconfig_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_networkconfig_modification.rules"
    # If the audit_rules_networkconfig_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/sysconfig/network" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sysconfig/network $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sysconfig/network$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Attempts to Alter Process and Session Initiation Information   [ref]

The audit system already collects process information for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d in order to watch for attempted manual edits of files involved in storing such process information: 
-w /var/run/utmp -p wa -k session
-w /var/log/btmp -p wa -k session
-w /var/log/wtmp -p wa -k session
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file in order to watch for attempted manual edits of files involved in storing such process information: 
-w /var/run/utmp -p wa -k session
-w /var/log/btmp -p wa -k session
-w /var/log/wtmp -p wa -k session
Rationale:
Manual editing of these files may indicate nefarious activity, such as an attacker attempting to remove evidence of an intrusion.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_session_events
Identifiers:

CCE-27301-1

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
ism0582, 0584, 05885, 0586, 0846, 0957
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAU-2(d), AU-12(c), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.3
app-srg-ctrSRG-APP-000505-CTR-001285
anssiR73
cis5.2.3.11
pcidss410.2.1.3

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /var/run/utmp already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/var/run/utmp\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key session
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)session$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/session.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/session.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /var/run/utmp in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /var/run/utmp -p wa -k session
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /var/run/utmp already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/var/run/utmp\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /var/run/utmp in /etc/audit/audit.rules
  lineinfile:
    line: -w /var/run/utmp -p wa -k session
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /var/log/btmp already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/var/log/btmp\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key session
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)session$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/session.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/session.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /var/log/btmp in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /var/log/btmp -p wa -k session
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /var/log/btmp already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/var/log/btmp\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /var/log/btmp in /etc/audit/audit.rules
  lineinfile:
    line: -w /var/log/btmp -p wa -k session
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /var/log/wtmp already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/var/log/wtmp\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key session
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)session$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/session.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/session.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /var/log/wtmp in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /var/log/wtmp -p wa -k session
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /var/log/wtmp already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/var/log/wtmp\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /var/log/wtmp in /etc/audit/audit.rules
  lineinfile:
    line: -w /var/log/wtmp -p wa -k session
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27301-1
  - CJIS-5.4.1.1
  - NIST-800-171-3.1.7
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.3
  - PCI-DSSv4-10.2.1.3
  - audit_rules_session_events
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/var/run/utmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/run/utmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/run/utmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/run/utmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/session.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/var/run/utmp" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/session.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/session.rules"
    # If the session.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/var/run/utmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/run/utmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/run/utmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/run/utmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/var/log/btmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/btmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/btmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/btmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/session.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/var/log/btmp" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/session.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/session.rules"
    # If the session.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/var/log/btmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/btmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/btmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/btmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/var/log/wtmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/wtmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/wtmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/wtmp -p wa -k session" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/session.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/var/log/wtmp" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/session.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/session.rules"
    # If the session.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/var/log/wtmp" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/var/log/wtmp $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/var/log/wtmp$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /var/log/wtmp -p wa -k session" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---


apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ %0A-w%20/var/run/utmp%20-p%20wa%20-k%20session%0A-w%20/var/log/btmp%20-p%20wa%20-k%20session%0A-w%20/var/log/wtmp%20-p%20wa%20-k%20session%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-audit-session-events.rules
        overwrite: true

Rule   Ensure auditd Collects System Administrator Actions   [ref]

At a minimum, the audit system should collect administrator actions for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d: 
-w /etc/sudoers -p wa -k actions
-w /etc/sudoers.d/ -p wa -k actions
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file: 
-w /etc/sudoers -p wa -k actions
-w /etc/sudoers.d/ -p wa -k actions
Rationale:
The actions taken by system administrators should be audited to keep a record of what was executed on the system, as well as, for accountability purposes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_sysadmin_actions
Identifiers:

CCE-27461-3

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000126, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistAC-2(7)(b), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.2, Req-10.2.5.b
os-srgSRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221
app-srg-ctrSRG-APP-000026-CTR-000070, SRG-APP-000027-CTR-000075, SRG-APP-000028-CTR-000080, SRG-APP-000291-CTR-000675, SRG-APP-000292-CTR-000680, SRG-APP-000293-CTR-000685, SRG-APP-000294-CTR-000690, SRG-APP-000319-CTR-000745, SRG-APP-000320-CTR-000750, SRG-APP-000509-CTR-001305
stigidRHEL-07-030700
anssiR73
cis5.2.3.1
pcidss410.2.1.5
stigrefSV-204549r853953_rule

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/sudoers already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/sudoers\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/sudoers in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/sudoers -p wa -k actions
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/sudoers already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/sudoers\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key actions
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)actions$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/actions.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/actions.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/sudoers in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/sudoers -p wa -k actions
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/sudoers.d/ already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/sudoers.d/\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/sudoers.d/ in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/sudoers.d/ -p wa -k actions
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check if watch rule for /etc/sudoers.d/ already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/sudoers.d/\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key actions
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)actions$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use /etc/audit/rules.d/actions.rules as the recipient for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/actions.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Add watch rule for /etc/sudoers.d/ in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/sudoers.d/ -p wa -k actions
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-27461-3
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030700
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(7)(b)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.2
  - PCI-DSS-Req-10.2.5.b
  - PCI-DSSv4-10.2.1.5
  - audit_rules_sysadmin_actions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/sudoers" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers -p wa -k actions" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/actions.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/sudoers" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/actions.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/actions.rules"
    # If the actions.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/sudoers" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers -p wa -k actions" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/sudoers.d/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers.d/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers.d/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers.d/ -p wa -k actions" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/actions.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/sudoers.d/" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/actions.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/actions.rules"
    # If the actions.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/sudoers.d/" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/sudoers.d/ $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/sudoers.d/$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/sudoers.d/ -p wa -k actions" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ -w%20/etc/sudoers.d/%20-p%20wa%20-k%20actions%0A-w%20/etc/sudoers%20-p%20wa%20-k%20actions%0A }}
        mode: 0600
        path: /etc/audit/rules.d/75-audit-sysadmin-actions.rules
        overwrite: true

Rule   Shutdown System When Auditing Failures Occur   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to to the bottom of a file with suffix .rules in the directory /etc/audit/rules.d: 
-f 2
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to the bottom of the /etc/audit/audit.rules file: 
-f 2
Rationale:
It is critical for the appropriate personnel to be aware if a system is at risk of failing to process audit logs as required. Without this notification, the security personnel may be unaware of an impending failure of the audit capability, and system operation may be adversely affected.

Audit processing failures include software/hardware errors, failures in the audit capturing mechanisms, and audit storage capacity being reached or exceeded.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_system_shutdown
Identifiers:

CCE-80997-0

References:
cis-csc1, 14, 15, 16, 3, 5, 6
cobit5APO11.04, BAI03.05, DSS05.04, DSS05.07, MEA02.01
cui3.3.1, 3.3.4
disaCCI-000139, CCI-000140
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1
nistAU-5(b), SC-24, CM-6(a)
nist-csfPR.PT-1
os-srgSRG-OS-000046-GPOS-00022, SRG-OS-000047-GPOS-00023
stigidRHEL-07-030010
stigrefSV-204504r880761_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80997-0
  - DISA-STIG-RHEL-07-030010
  - NIST-800-171-3.3.1
  - NIST-800-171-3.3.4
  - NIST-800-53-AU-5(b)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-24
  - audit_rules_system_shutdown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy
- name: XCCDF Value var_audit_failure_mode # promote to variable
  set_fact:
    var_audit_failure_mode: !!str 2
  tags:
    - always

- name: Collect all files from /etc/audit/rules.d with .rules extension
  find:
    paths: /etc/audit/rules.d/
    patterns: '*.rules'
  register: find_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80997-0
  - DISA-STIG-RHEL-07-030010
  - NIST-800-171-3.3.1
  - NIST-800-171-3.3.4
  - NIST-800-53-AU-5(b)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-24
  - audit_rules_system_shutdown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Remove the -f option from all Audit config files
  lineinfile:
    path: '{{ item }}'
    regexp: ^\s*(?:-f)\s+.*$
    state: absent
  loop: '{{ find_rules_d.files | map(attribute=''path'') | list + [''/etc/audit/audit.rules'']
    }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80997-0
  - DISA-STIG-RHEL-07-030010
  - NIST-800-171-3.3.1
  - NIST-800-171-3.3.4
  - NIST-800-53-AU-5(b)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-24
  - audit_rules_system_shutdown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add Audit -f option into /etc/audit/rules.d/immutable.rules and /etc/audit/audit.rules
  lineinfile:
    path: '{{ item }}'
    create: true
    line: -f {{ var_audit_failure_mode }}
  loop:
  - /etc/audit/audit.rules
  - /etc/audit/rules.d/immutable.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80997-0
  - DISA-STIG-RHEL-07-030010
  - NIST-800-171-3.3.1
  - NIST-800-171-3.3.4
  - NIST-800-53-AU-5(b)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-24
  - audit_rules_system_shutdown
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

var_audit_failure_mode='2'


# Traverse all of:
#
# /etc/audit/audit.rules,			(for auditctl case)
# /etc/audit/rules.d/*.rules			(for augenrules case)
find /etc/audit /etc/audit/rules.d -maxdepth 1 -type f -name '*.rules' -exec sed -i '/-f[[:space:]]\+.*/d' {} ';'

for AUDIT_FILE in "/etc/audit/audit.rules" "/etc/audit/rules.d/immutable.rules"
do
	echo '' >> $AUDIT_FILE
	echo '# Set the audit.rules configuration to halt system upon audit failure per security requirements' >> $AUDIT_FILE
	echo "-f $var_audit_failure_mode" >> $AUDIT_FILE
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify User/Group Information - /etc/group   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes: 

-w /etc/group -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes: 

-w /etc/group -p wa -k audit_rules_usergroup_modification
Rationale:
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_group
Identifiers:

CCE-80433-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000018, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.5
os-srgSRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000503-CTR-001275
stigidRHEL-07-030871
anssiR73
cis5.2.3.8
pcidss410.2.1.5
stigrefSV-204565r853979_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/group already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/group\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_usergroup_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_usergroup_modification.rules as the recipient
    for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_usergroup_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/group in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/group -p wa -k audit_rules_usergroup_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/group already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/group\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/group in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/group -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-80433-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030871
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_group
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/group" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/group $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/group$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/group -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/group" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/group" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/group $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/group$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/group -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify User/Group Information - /etc/gshadow   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes: 

-w /etc/gshadow -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes: 

-w /etc/gshadow -p wa -k audit_rules_usergroup_modification
Rationale:
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_gshadow
Identifiers:

CCE-80432-8

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000018, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.5
os-srgSRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000503-CTR-001275
stigidRHEL-07-030872
anssiR73
cis5.2.3.8
pcidss410.2.1.5
stigrefSV-204566r853980_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/gshadow already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/gshadow\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_usergroup_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_usergroup_modification.rules as the recipient
    for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_usergroup_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/gshadow in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/gshadow -p wa -k audit_rules_usergroup_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/gshadow already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/gshadow\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/gshadow in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/gshadow -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-80432-8
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030872
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/gshadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/gshadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/gshadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/gshadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/gshadow" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/gshadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/gshadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/gshadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/gshadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify User/Group Information - /etc/security/opasswd   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes: 

-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes: 

-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
Rationale:
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_opasswd
Identifiers:

CCE-80430-2

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000018, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.5
os-srgSRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000496-CTR-001240, SRG-APP-000497-CTR-001245, SRG-APP-000498-CTR-001250, SRG-APP-000503-CTR-001275
stigidRHEL-07-030874
anssiR73
cis5.2.3.8
pcidss410.2.1.5
stigrefSV-204568r853982_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/security/opasswd already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/security/opasswd\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_usergroup_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_usergroup_modification.rules as the recipient
    for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_usergroup_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/security/opasswd in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/security/opasswd already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/security/opasswd\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/security/opasswd in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-80430-2
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030874
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/security/opasswd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/security/opasswd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/security/opasswd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/security/opasswd" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/security/opasswd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/security/opasswd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/security/opasswd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify User/Group Information - /etc/passwd   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes: 

-w /etc/passwd -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes: 

-w /etc/passwd -p wa -k audit_rules_usergroup_modification
Rationale:
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_passwd
Identifiers:

CCE-80435-1

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000018, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.5
os-srgSRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000304-GPOS-00121, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221, SRG-OS-000274-GPOS-00104, SRG-OS-000275-GPOS-00105, SRG-OS-000276-GPOS-00106, SRG-OS-000277-GPOS-00107
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000503-CTR-001275
stigidRHEL-07-030870
anssiR73
cis5.2.3.8
pcidss410.2.1.5
stigrefSV-204564r853978_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/passwd already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/passwd\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_usergroup_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_usergroup_modification.rules as the recipient
    for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_usergroup_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/passwd in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/passwd -p wa -k audit_rules_usergroup_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/passwd already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/passwd\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/passwd in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/passwd -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-80435-1
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030870
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/passwd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/passwd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/passwd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/passwd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/passwd" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/passwd" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/passwd $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/passwd$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/passwd -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Record Events that Modify User/Group Information - /etc/shadow   [ref]

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes: 

-w /etc/shadow -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes: 

-w /etc/shadow -p wa -k audit_rules_usergroup_modification
Rationale:
In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification_shadow
Identifiers:

CCE-80431-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.1.7
disaCCI-000018, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-001403, CCI-001404, CCI-001405, CCI-001683, CCI-001684, CCI-001685, CCI-001686, CCI-002130, CCI-002132, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.2.2, 4.3.3.3.9, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.8, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.1.2, A.6.2.1, A.6.2.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-004-6 R2.2.2, CIP-004-6 R2.2.3, CIP-007-3 R.1.3, CIP-007-3 R5, CIP-007-3 R5.1.1, CIP-007-3 R5.1.3, CIP-007-3 R5.2.1, CIP-007-3 R5.2.3
nistAC-2(4), AU-2(d), AU-12(c), AC-6(9), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-1, PR.AC-3, PR.AC-4, PR.AC-6, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.2.5
os-srgSRG-OS-000004-GPOS-00004, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000304-GPOS-00121, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000470-GPOS-00214, SRG-OS-000471-GPOS-00215, SRG-OS-000239-GPOS-00089, SRG-OS-000240-GPOS-00090, SRG-OS-000241-GPOS-00091, SRG-OS-000303-GPOS-00120, SRG-OS-000466-GPOS-00210, SRG-OS-000476-GPOS-00221
app-srg-ctrSRG-APP-000495-CTR-001235, SRG-APP-000499-CTR-001255, SRG-APP-000503-CTR-001275
stigidRHEL-07-030873
anssiR73
cis5.2.3.8
pcidss410.2.1.5
stigrefSV-204567r853981_rule

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/shadow already exists in /etc/audit/rules.d/
  find:
    paths: /etc/audit/rules.d
    contains: ^\s*-w\s+/etc/shadow\s+-p\s+wa(\s|$)+
    patterns: '*.rules'
  register: find_existing_watch_rules_d
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Search /etc/audit/rules.d for other rules with specified key audit_rules_usergroup_modification
  find:
    paths: /etc/audit/rules.d
    contains: ^.*(?:-F key=|-k\s+)audit_rules_usergroup_modification$
    patterns: '*.rules'
  register: find_watch_key
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use /etc/audit/rules.d/audit_rules_usergroup_modification.rules as the recipient
    for the rule
  set_fact:
    all_files:
    - /etc/audit/rules.d/audit_rules_usergroup_modification.rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched == 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Use matched file as the recipient for the rule
  set_fact:
    all_files:
    - '{{ find_watch_key.files | map(attribute=''path'') | list | first }}'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_watch_key.matched is defined and find_watch_key.matched > 0 and find_existing_watch_rules_d.matched
    is defined and find_existing_watch_rules_d.matched == 0
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/shadow in /etc/audit/rules.d/
  lineinfile:
    path: '{{ all_files[0] }}'
    line: -w /etc/shadow -p wa -k audit_rules_usergroup_modification
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_rules_d.matched is defined and find_existing_watch_rules_d.matched
    == 0
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Check if watch rule for /etc/shadow already exists in /etc/audit/audit.rules
  find:
    paths: /etc/audit/
    contains: ^\s*-w\s+/etc/shadow\s+-p\s+wa(\s|$)+
    patterns: audit.rules
  register: find_existing_watch_audit_rules
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy

- name: Add watch rule for /etc/shadow in /etc/audit/audit.rules
  lineinfile:
    line: -w /etc/shadow -p wa -k audit_rules_usergroup_modification
    state: present
    dest: /etc/audit/audit.rules
    create: true
    mode: '0640'
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - find_existing_watch_audit_rules.matched is defined and find_existing_watch_audit_rules.matched
    == 0
  tags:
  - CCE-80431-0
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030873
  - NIST-800-171-3.1.7
  - NIST-800-53-AC-2(4)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-10.2.1.5
  - audit_rules_usergroup_modification_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

# Perform the remediation for both possible tools: 'auditctl' and 'augenrules'

# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()


# If the audit tool is 'auditctl', then add '/etc/audit/audit.rules'
# into the list of files to be inspected
files_to_inspect+=('/etc/audit/audit.rules')

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/shadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/shadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/shadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/shadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done
# Create a list of audit *.rules files that should be inspected for presence and correctness
# of a particular audit rule. The scheme is as follows:
#
# -----------------------------------------------------------------------------------------
# Tool used to load audit rules	| Rule already defined	|  Audit rules file to inspect	  |
# -----------------------------------------------------------------------------------------
#	auditctl		|     Doesn't matter	|  /etc/audit/audit.rules	  |
# -----------------------------------------------------------------------------------------
# 	augenrules		|          Yes		|  /etc/audit/rules.d/*.rules	  |
# 	augenrules		|          No		|  /etc/audit/rules.d/$key.rules  |
# -----------------------------------------------------------------------------------------
files_to_inspect=()

# If the audit is 'augenrules', then check if rule is already defined
# If rule is defined, add '/etc/audit/rules.d/*.rules' to list of files for inspection.
# If rule isn't defined, add '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' to list of files for inspection.
readarray -t matches < <(grep -HP "[\s]*-w[\s]+/etc/shadow" /etc/audit/rules.d/*.rules)

# For each of the matched entries
for match in "${matches[@]}"
do
    # Extract filepath from the match
    rulesd_audit_file=$(echo $match | cut -f1 -d ':')
    # Append that path into list of files for inspection
    files_to_inspect+=("$rulesd_audit_file")
done
# Case when particular audit rule isn't defined yet
if [ "${#files_to_inspect[@]}" -eq "0" ]
then
    # Append '/etc/audit/rules.d/audit_rules_usergroup_modification.rules' into list of files for inspection
    key_rule_file="/etc/audit/rules.d/audit_rules_usergroup_modification.rules"
    # If the audit_rules_usergroup_modification.rules file doesn't exist yet, create it with correct permissions
    if [ ! -e "$key_rule_file" ]
    then
        touch "$key_rule_file"
        chmod 0640 "$key_rule_file"
    fi
    files_to_inspect+=("$key_rule_file")
fi

# Finally perform the inspection and possible subsequent audit rule
# correction for each of the files previously identified for inspection
for audit_rules_file in "${files_to_inspect[@]}"
do
    # Check if audit watch file system object rule for given path already present
    if grep -q -P -- "^[\s]*-w[\s]+/etc/shadow" "$audit_rules_file"
    then
        # Rule is found => verify yet if existing rule definition contains
        # all of the required access type bits

        # Define BRE whitespace class shortcut
        sp="[[:space:]]"
        # Extract current permission access types (e.g. -p [r|w|x|a] values) from audit rule
        current_access_bits=$(sed -ne "s#$sp*-w$sp\+/etc/shadow $sp\+-p$sp\+\([rxwa]\{1,4\}\).*#\1#p" "$audit_rules_file")
        # Split required access bits string into characters array
        # (to check bit's presence for one bit at a time)
        for access_bit in $(echo "wa" | grep -o .)
        do
            # For each from the required access bits (e.g. 'w', 'a') check
            # if they are already present in current access bits for rule.
            # If not, append that bit at the end
            if ! grep -q "$access_bit" <<< "$current_access_bits"
            then
                # Concatenate the existing mask with the missing bit
                current_access_bits="$current_access_bits$access_bit"
            fi
        done
        # Propagate the updated rule's access bits (original + the required
        # ones) back into the /etc/audit/audit.rules file for that rule
        sed -i "s#\($sp*-w$sp\+/etc/shadow$sp\+-p$sp\+\)\([rxwa]\{1,4\}\)\(.*\)#\1$current_access_bits\3#" "$audit_rules_file"
    else
        # Rule isn't present yet. Append it at the end of $audit_rules_file file
        # with proper key

        echo "-w /etc/shadow -p wa -k audit_rules_usergroup_modification" >> "$audit_rules_file"
    fi
done

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Configure auditd Data Retention   Group contains 2 rules
[ref]   The audit system writes data to /var/log/audit/audit.log. By default, auditd rotates 5 logs by size (6MB), retaining a maximum of 30MB of data in total, and refuses to write entries when the disk is too full. This minimizes the risk of audit data filling its partition and impacting other services. This also minimizes the risk of the audit daemon temporarily disabling the system if it cannot write audit log (which it can be configured to do). For a busy system or a system which is thoroughly auditing system activity, the default settings for data retention may be insufficient. The log file size needed will depend heavily on what types of events are being audited. First configure auditing to log all the events of interest. Then monitor the log size manually for awhile to determine what file size will allow you to keep the required data for the correct time period.

Using a dedicated partition for /var/log/audit prevents the auditd logs from disrupting system functionality if they fill, and, more importantly, prevents other activity in /var from filling the partition and stopping the audit trail. (The audit logs are size-limited and therefore unlikely to grow without bound unless configured to do so.) Some machines may have requirements that no actions occur which cannot be audited. If this is the case, then auditd can be configured to halt the machine if it runs out of space. Note: Since older logs are rotated, configuring auditd this way does not prevent older logs from being rotated away before they can be viewed. If your system is configured to halt when logging cannot be performed, make sure this can never happen under normal circumstances! Ensure that /var/log/audit is on its own partition, and that this partition is larger than the maximum amount of data auditd will retain normally.

Rule   Configure auditd to use audispd's syslog plugin   [ref]

To configure the auditd service to use the syslog plug-in of the audispd audit event multiplexor, set the active line in /etc/audisp/plugins.d/syslog.conf to yes. Restart the auditd service: 
$ sudo service auditd restart
Rationale:
The auditd service does not include the ability to send audit records to a centralized server for management directly. It does, however, include a plug-in for audit event multiplexor (audispd) to pass audit records to the local syslog server.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_auditd_audispd_syslog_plugin_activated
Identifiers:

CCE-27341-7

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 3, 4, 5, 6, 7, 8
cjis5.4.1.1
cobit5APO11.04, APO12.06, BAI03.05, BAI08.02, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS05.04, DSS05.07, MEA02.01
cui3.3.1
disaCCI-000136
hipaa164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(B), 164.308(a)(5)(ii)(C), 164.308(a)(6)(ii), 164.308(a)(8), 164.310(d)(2)(iii), 164.312(b), 164.314(a)(2)(i)(C), 164.314(a)(2)(iii)
isa-62443-20094.2.3.10, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.16.1.4, A.16.1.5, A.16.1.7
nistAU-4(1), CM-6(a)
nist-csfDE.AE-3, DE.AE-5, PR.PT-1, RS.AN-1, RS.AN-4
osppFAU_GEN.1.1.c
pcidssReq-10.5.3
os-srgSRG-OS-000479-GPOS-00224, SRG-OS-000342-GPOS-00133
pcidss410.3.3

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27341-7
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AU-4(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.3
  - PCI-DSSv4-10.3.3
  - auditd_audispd_syslog_plugin_activated
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Enable syslog plugin
  lineinfile:
    dest: /etc/audisp/plugins.d/syslog.conf
    regexp: ^active
    line: active = yes
    create: true
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27341-7
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AU-4(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.3
  - PCI-DSSv4-10.3.3
  - auditd_audispd_syslog_plugin_activated
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

var_syslog_active="yes"

AUDISP_SYSLOGCONFIG=/etc/audisp/plugins.d/syslog.conf

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^active")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_syslog_active"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^active\\>" "$AUDISP_SYSLOGCONFIG"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^active\\>.*/$escaped_formatted_output/gi" "$AUDISP_SYSLOGCONFIG"
else
    if [[ -s "$AUDISP_SYSLOGCONFIG" ]] && [[ -n "$(tail -c 1 -- "$AUDISP_SYSLOGCONFIG" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "$AUDISP_SYSLOGCONFIG"
    fi
    cce="CCE-27341-7"
    printf '# Per %s: Set %s in %s\n' "${cce}" "${formatted_output}" "$AUDISP_SYSLOGCONFIG" >> "$AUDISP_SYSLOGCONFIG"
    printf '%s\n' "$formatted_output" >> "$AUDISP_SYSLOGCONFIG"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Configure auditd flush priority   [ref]

The auditd service can be configured to synchronously write audit event data to disk. Add or correct the following line in /etc/audit/auditd.conf to ensure that audit event data is fully synchronized with the log files on the disk: 
flush = data
Rationale:
Audit data should be synchronously written to disk to ensure log integrity. These parameters assure that all audit event data is fully synchronized with the log files on the disk.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_auditd_data_retention_flush
Identifiers:

CCE-27331-8

References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, BAI03.05, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.3.1
disaCCI-001576
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3)(ii)(A), 164.308(a)(5)(ii)(C), 164.312(a)(2)(i), 164.312(b), 164.312(d), 164.312(e)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2
iso27001-2013A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2
nerc-cipCIP-004-6 R2.2.3, CIP-004-6 R3.3, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, CIP-007-3 R6.5
nistAU-11, CM-6(a)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.PT-1
os-srgSRG-OS-000480-GPOS-00227

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27331-8
  - NIST-800-171-3.3.1
  - NIST-800-53-AU-11
  - NIST-800-53-CM-6(a)
  - auditd_data_retention_flush
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_auditd_flush # promote to variable
  set_fact:
    var_auditd_flush: !!str data
  tags:
    - always

- name: Configure auditd Flush Priority
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: ^\s*flush\s*=\s*.*$
    line: flush = {{ var_auditd_flush }}
    state: present
    create: true
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CCE-27331-8
  - NIST-800-171-3.3.1
  - NIST-800-53-AU-11
  - NIST-800-53-CM-6(a)
  - auditd_data_retention_flush
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && rpm --quiet -q audit; then

var_auditd_flush='data'


AUDITCONFIG=/etc/audit/auditd.conf

# if flush is present, flush param edited to var_auditd_flush
# else flush param is defined by var_auditd_flush
#
# the freq param is only used for values 'incremental' and 'incremental_async' and will be
# commented out if flush != incremental or flush != incremental_async
#
# if flush == incremental or flush == incremental_async && freq param is not defined, it 
# will be defined as the package-default value of 20

grep -q ^flush $AUDITCONFIG && \
  sed -i 's/^flush.*/flush = '"$var_auditd_flush"'/g' $AUDITCONFIG
if ! [ $? -eq 0 ]; then
  echo "flush = $var_auditd_flush" >> $AUDITCONFIG
fi

if ! [ "$var_auditd_flush" == "incremental" ] && ! [ "$var_auditd_flush" == "incremental_async" ]; then
  sed -i 's/^freq/##freq/g' $AUDITCONFIG
elif [ "$var_auditd_flush" == "incremental" ] || [ "$var_auditd_flush" == "incremental_async" ]; then
  grep -q freq $AUDITCONFIG && \
    sed -i 's/^#\+freq/freq/g' $AUDITCONFIG
  if ! [ $? -eq 0 ]; then
    echo "freq = 20" >> $AUDITCONFIG
  fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,{{ %23%0A%23%20This%20file%20controls%20the%20configuration%20of%20the%20audit%20daemon%0A%23%0A%0Alocal_events%20%3D%20yes%0Awrite_logs%20%3D%20yes%0Alog_file%20%3D%20/var/log/audit/audit.log%0Alog_group%20%3D%20root%0Alog_format%20%3D%20ENRICHED%0Aflush%20%3D%20%7B%7B.var_auditd_flush%7D%7D%0Afreq%20%3D%2050%0Amax_log_file%20%3D%20%7B%7B.var_auditd_max_log_file%7D%7D%0Anum_logs%20%3D%20%7B%7B.var_auditd_num_logs%7D%7D%0Apriority_boost%20%3D%204%0Aname_format%20%3D%20hostname%0A%23%23name%20%3D%20mydomain%0Amax_log_file_action%20%3D%20%7B%7B.var_auditd_max_log_file_action%7D%7D%0Aspace_left%20%3D%20%7B%7B.var_auditd_space_left%7D%7D%0Aspace_left_action%20%3D%20%7B%7B.var_auditd_space_left_action%7D%7D%0Averify_email%20%3D%20yes%0Aaction_mail_acct%20%3D%20%7B%7B.var_auditd_action_mail_acct%7D%7D%0Aadmin_space_left%20%3D%2050%0Aadmin_space_left_action%20%3D%20syslog%0Adisk_full_action%20%3D%20%7B%7B.var_auditd_disk_full_action%7D%7D%0Adisk_error_action%20%3D%20%7B%7B.var_auditd_disk_error_action%7D%7D%0Ause_libwrap%20%3D%20yes%0A%23%23tcp_listen_port%20%3D%2060%0Atcp_listen_queue%20%3D%205%0Atcp_max_per_addr%20%3D%201%0A%23%23tcp_client_ports%20%3D%201024-65535%0Atcp_client_max_idle%20%3D%200%0Atransport%20%3D%20TCP%0Akrb5_principal%20%3D%20auditd%0A%23%23krb5_key_file%20%3D%20/etc/audit/audit.key%0Adistribute_network%20%3D%20no%0Aq_depth%20%3D%20400%0Aoverflow_action%20%3D%20syslog%0Amax_restarts%20%3D%2010%0Aplugin_dir%20%3D%20/etc/audit/plugins.d }}
        mode: 0640
        path: /etc/audit/auditd.conf
        overwrite: true

Rule   Enable auditd Service   [ref]

The auditd service is an essential userspace component of the Linux Auditing System, as it is responsible for writing audit records to disk. The auditd service can be enabled with the following command: 
$ sudo systemctl enable auditd.service
Rationale:
Without establishing what type of events occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack. Ensuring the auditd service is active ensures audit records generated by the kernel are appropriately recorded.

Additionally, a properly configured audit subsystem ensures that actions of individual system users can be uniquely traced to those users so they can be held accountable for their actions.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_auditd_enabled
Identifiers:

CCE-27407-6

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 2, 3, 4, 5, 6, 7, 8, 9
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.03, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS03.05, DSS05.02, DSS05.03, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.3.1, 3.3.2, 3.3.6
disaCCI-000126, CCI-000130, CCI-000131, CCI-000132, CCI-000133, CCI-000134, CCI-000135, CCI-000154, CCI-000158, CCI-000172, CCI-000366, CCI-001464, CCI-001487, CCI-001814, CCI-001875, CCI-001876, CCI-001877, CCI-002884, CCI-001878, CCI-001879, CCI-001880, CCI-001881, CCI-001882, CCI-001889, CCI-001914, CCI-000169
hipaa164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(C), 164.310(a)(2)(iv), 164.310(d)(2)(iii), 164.312(b)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 6.2, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.7, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nerc-cipCIP-004-6 R3.3, CIP-007-3 R6.5
nistAC-2(g), AU-3, AU-10, AU-2(d), AU-12(c), AU-14(1), AC-6(9), CM-6(a), SI-4(23)
nist-csfDE.AE-3, DE.AE-5, DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1
pcidssReq-10.1
os-srgSRG-OS-000062-GPOS-00031, SRG-OS-000037-GPOS-00015, SRG-OS-000038-GPOS-00016, SRG-OS-000039-GPOS-00017, SRG-OS-000040-GPOS-00018, SRG-OS-000041-GPOS-00019, SRG-OS-000042-GPOS-00021, SRG-OS-000051-GPOS-00024, SRG-OS-000054-GPOS-00025, SRG-OS-000122-GPOS-00063, SRG-OS-000254-GPOS-00095, SRG-OS-000255-GPOS-00096, SRG-OS-000337-GPOS-00129, SRG-OS-000348-GPOS-00136, SRG-OS-000349-GPOS-00137, SRG-OS-000350-GPOS-00138, SRG-OS-000351-GPOS-00139, SRG-OS-000352-GPOS-00140, SRG-OS-000353-GPOS-00141, SRG-OS-000354-GPOS-00142, SRG-OS-000358-GPOS-00145, SRG-OS-000365-GPOS-00152, SRG-OS-000392-GPOS-00172, SRG-OS-000475-GPOS-00220
app-srg-ctrSRG-APP-000095-CTR-000170, SRG-APP-000409-CTR-000990, SRG-APP-000508-CTR-001300, SRG-APP-000510-CTR-001310
stigidRHEL-07-030000
anssiR33, R73
cis5.2.1.4
pcidss410.2.1
stigrefSV-204503r603261_rule


[customizations.services]
enabled = ["auditd"]

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27407-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030000
  - NIST-800-171-3.3.1
  - NIST-800-171-3.3.2
  - NIST-800-171-3.3.6
  - NIST-800-53-AC-2(g)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-14(1)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-AU-3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-4(23)
  - PCI-DSS-Req-10.1
  - PCI-DSSv4-10.2.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_auditd_enabled

- name: Enable auditd Service - Enable service auditd
  block:

  - name: Gather the package facts
    package_facts:
      manager: auto

  - name: Enable auditd Service - Enable Service auditd
    ansible.builtin.systemd:
      name: auditd
      enabled: true
      state: started
      masked: false
    when:
    - '"audit" in ansible_facts.packages'
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"audit" in ansible_facts.packages'
  tags:
  - CCE-27407-6
  - CJIS-5.4.1.1
  - DISA-STIG-RHEL-07-030000
  - NIST-800-171-3.3.1
  - NIST-800-171-3.3.2
  - NIST-800-171-3.3.6
  - NIST-800-53-AC-2(g)
  - NIST-800-53-AC-6(9)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-12(c)
  - NIST-800-53-AU-14(1)
  - NIST-800-53-AU-2(d)
  - NIST-800-53-AU-3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-4(23)
  - PCI-DSS-Req-10.1
  - PCI-DSSv4-10.2.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_auditd_enabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include enable_auditd

class enable_auditd {
  service {'auditd':
    enable => true,
    ensure => 'running',
  }
}

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q audit; }; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'auditd.service'
"$SYSTEMCTL_EXEC" start 'auditd.service'
"$SYSTEMCTL_EXEC" enable 'auditd.service'

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: auditd.service
        enabled: true

Rule   Enable Auditing for Processes Which Start Prior to the Audit Daemon   [ref]

To ensure all processes can be audited, even those which start prior to the audit daemon, add the argument audit=1 to the default GRUB 2 command line for the Linux operating system. To ensure that audit=1 is added as a kernel command line argument to newly installed kernels, add audit=1 to the default Grub2 command line for Linux operating systems. Modify the line within /etc/default/grub as shown below: 
GRUB_CMDLINE_LINUX="... audit=1 ..."
Run the following command to update command line for already installed kernels:
# grubby --update-kernel=ALL --args="audit=1"
Rationale:
Each process on the system carries an "auditable" flag which indicates whether its activities can be audited. Although auditd takes care of enabling this for all processes which launch after it does, adding the kernel argument ensures it is set for every process during boot.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_grub2_audit_argument
Identifiers:

CCE-27212-0

References:
cis-csc1, 11, 12, 13, 14, 15, 16, 19, 3, 4, 5, 6, 7, 8
cjis5.4.1.1
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO12.06, APO13.01, BAI03.05, BAI08.02, DSS01.04, DSS02.02, DSS02.04, DSS02.07, DSS03.01, DSS05.02, DSS05.03, DSS05.04, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
cui3.3.1
disaCCI-001464, CCI-000130, CCI-000135, CCI-000169, CCI-000172, CCI-002884
hipaa164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(C), 164.310(a)(2)(iv), 164.310(d)(2)(iii), 164.312(b)
isa-62443-20094.2.3.10, 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.3.6.6, 4.3.4.4.7, 4.3.4.5.6, 4.3.4.5.7, 4.3.4.5.8, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 1.13, SR 2.10, SR 2.11, SR 2.12, SR 2.6, SR 2.8, SR 2.9, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 6.1, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.13.1.1, A.13.2.1, A.14.1.3, A.15.2.1, A.15.2.2, A.16.1.4, A.16.1.5, A.16.1.7, A.6.2.1, A.6.2.2
nistAC-17(1), AU-14(1), AU-10, CM-6(a), IR-5(1)
nist-csfDE.AE-3, DE.AE-5, ID.SC-4, PR.AC-3, PR.PT-1, PR.PT-4, RS.AN-1, RS.AN-4
osppFAU_GEN.1
pcidssReq-10.3
os-srgSRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000473-GPOS-00218, SRG-OS-000254-GPOS-00095
cis5.2.1.2
pcidss410.7.2

[customizations.kernel]
append = "audit=1"

Complexity:medium
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy

- name: Check audit argument exists
  command: grep '^\s*GRUB_CMDLINE_LINUX=.*audit=' /etc/default/grub
  failed_when: false
  register: argcheck
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy

- name: Check audit argument exists
  command: grep '^\s*GRUB_CMDLINE_LINUX=' /etc/default/grub
  failed_when: false
  register: linecheck
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy

- name: Add audit argument
  ansible.builtin.lineinfile:
    line: GRUB_CMDLINE_LINUX="audit=1 "
    state: present
    dest: /etc/default/grub
    create: true
    mode: '0644'
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  - argcheck is not skipped and linecheck is not skipped and argcheck.rc != 0 and
    linecheck.rc != 0
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy

- name: Replace existing audit argument
  replace:
    path: /etc/default/grub
    regexp: audit=[a-zA-Z0-9,]+
    replace: audit=1
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  - argcheck is not skipped and linecheck is not skipped and argcheck.rc == 0 and
    linecheck.rc == 0
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy

- name: Add audit argument
  replace:
    path: /etc/default/grub
    regexp: (^\s*GRUB_CMDLINE_LINUX=.*)"
    replace: \1 audit=1"
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  - argcheck is not skipped and linecheck is not skipped and argcheck.rc != 0 and
    linecheck.rc == 0
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy

- name: Update grub defaults and the bootloader menu
  command: /sbin/grubby --update-kernel=ALL --args="audit=1"
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"grub2-common" in ansible_facts.packages'
  tags:
  - CCE-27212-0
  - CJIS-5.4.1.1
  - NIST-800-171-3.3.1
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AU-10
  - NIST-800-53-AU-14(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IR-5(1)
  - PCI-DSS-Req-10.3
  - PCI-DSSv4-10.7.2
  - grub2_audit_argument
  - low_disruption
  - low_severity
  - medium_complexity
  - reboot_required
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { rpm --quiet -q grub2-common; }; then

# Correct the form of default kernel command line in GRUB
if grep -q '^\s*GRUB_CMDLINE_LINUX=.*audit=.*"'  '/etc/default/grub' ; then
       # modify the GRUB command-line if an audit= arg already exists
       sed -i "s/\(^\s*GRUB_CMDLINE_LINUX=\".*\)audit=[^[:space:]]\+\(.*\"\)/\1audit=1\2/"  '/etc/default/grub'
# Add to already existing GRUB_CMDLINE_LINUX parameters
elif grep -q '^\s*GRUB_CMDLINE_LINUX='  '/etc/default/grub' ; then
       # no audit=arg is present, append it
       sed -i "s/\(^\s*GRUB_CMDLINE_LINUX=\".*\)\"/\1 audit=1\"/"  '/etc/default/grub'
# Add GRUB_CMDLINE_LINUX parameters line
else
       echo "GRUB_CMDLINE_LINUX=\"audit=1\"" >> '/etc/default/grub'
fi
grubby --update-kernel=ALL --args=audit=1

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Red Hat and Red Hat Enterprise Linux are either registered trademarks or trademarks of Red Hat, Inc. in the United States and other countries. All other names are registered trademarks or trademarks of their respective companies.