Guide to the Secure Configuration of Amazon Linux 2023

with profile CIS Amazon Linux 2023 Benchmark for Level 1 - Server
This profile defines a baseline that aligns to the "Level 1 - Server" configuration from the Center for Internet Security® Amazon Linux 2023 Benchmark™, v1.0.0, released 2023-06-26. This profile includes Center for Internet Security® Amazon Linux 2023 CIS Benchmarks™ content.
This guide presents a catalog of security-relevant configuration settings for Amazon Linux 2023. 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 TitleCIS Amazon Linux 2023 Benchmark for Level 1 - Server
Profile IDxccdf_org.ssgproject.content_profile_cis_server_l1

CPE Platforms

  • cpe:/o:amazon:amazon_linux:2023

Revision History

Current version: 0.1.76

  • draft (as of 2024-12-21)

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. Avahi Server
    2. Cron and At Daemons
    3. DHCP
    4. DNS Server
    5. FTP Server
    6. Web Server
    7. IMAP and POP3 Server
    8. LDAP
    9. Mail Server Software
    10. NFS and RPC
    11. Network Time Protocol
    12. Obsolete Services
    13. Print Support
    14. Proxy Server
    15. Samba(SMB) Microsoft Windows File Sharing Server
    16. SNMP Server
    17. SSH Server

Checklist

Group   Guide to the Secure Configuration of Amazon Linux 2023   Group contains 86 groups and 259 rules
Group   System Settings   Group contains 45 groups and 180 rules
[ref]   Contains rules that check correct system settings.
Group   Installing and Maintaining Software   Group contains 7 groups and 13 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 3 groups and 6 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 4 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 AIDE   Group contains 4 rules
[ref]   AIDE conducts integrity checks by comparing information about files with previously-gathered information. Ideally, the AIDE database is created immediately after initial system configuration, and then again after any software update. AIDE is highly configurable, with further configuration information located in /usr/share/doc/aide-VERSION .

Rule   Install AIDE   [ref]

The aide package can be installed with the following command:
$ sudo dnf install aide
Rationale:
The AIDE package must be installed if it is to be available for integrity checking.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_aide_installed
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 5, 7, 8, 9
cjis5.10.1.3
cobit5APO01.06, BAI01.06, BAI02.01, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS04.07, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.02, DSS06.06
disaCCI-002696, CCI-001744
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 4.1, SR 6.2, SR 7.6
ism1034, 1288, 1341, 1417
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.4.1, 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, A.14.2.7, A.15.2.1, A.8.2.3
nistCM-6(a)
nist-csfDE.CM-1, DE.CM-7, PR.DS-1, PR.DS-6, PR.DS-8, PR.IP-1, PR.IP-3
pcidssReq-11.5
os-srgSRG-OS-000445-GPOS-00199
anssiR76, R79
cis1.3.1
pcidss411.5.2


[[packages]]
name = "aide"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_aide_installed

- name: Ensure aide is installed
  package:
    name: aide
    state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_aide_installed

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

class install_aide {
  package { 'aide':
    ensure => 'installed',
  }
}

Rule   Build and Test AIDE Database   [ref]

Run the following command to generate a new database:
$ sudo /usr/sbin/aide --init
By default, the database will be written to the file /var/lib/aide/aide.db.new.gz. Storing the database, the configuration file /etc/aide.conf, and the binary /usr/sbin/aide (or hashes of these files), in a secure location (such as on read-only media) provides additional assurance about their integrity. The newly-generated database can be installed as follows:
$ sudo cp /var/lib/aide/aide.db.new.gz /var/lib/aide/aide.db.gz
To initiate a manual check, run the following command:
$ sudo /usr/sbin/aide --check
If this check produces any unexpected output, investigate.
Rationale:
For AIDE to be effective, an initial database of "known-good" information about files must be captured and it should be able to be verified against the installed files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_aide_build_database
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 5, 7, 8, 9
cjis5.10.1.3
cobit5APO01.06, BAI01.06, BAI02.01, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS04.07, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.02, DSS06.06
disaCCI-002696, CCI-001744
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 4.1, SR 6.2, SR 7.6
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.4.1, 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, A.14.2.7, A.15.2.1, A.8.2.3
nistCM-6(a)
nist-csfDE.CM-1, DE.CM-7, PR.DS-1, PR.DS-6, PR.DS-8, PR.IP-1, PR.IP-3
pcidssReq-11.5
os-srgSRG-OS-000445-GPOS-00199
anssiR76, R79
cis1.3.1
pcidss411.5.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Build and Test AIDE Database - Ensure AIDE Is Installed
  ansible.builtin.package:
    name: '{{ item }}'
    state: present
  with_items:
  - aide
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Build and Test AIDE Database - Build and Test AIDE Database
  ansible.builtin.command: /usr/sbin/aide --init
  changed_when: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Build and Test AIDE Database - Check Whether the Stock AIDE Database Exists
  ansible.builtin.stat:
    path: /var/lib/aide/aide.db.new.gz
  register: aide_database_stat
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Build and Test AIDE Database - Stage AIDE Database
  ansible.builtin.copy:
    src: /var/lib/aide/aide.db.new.gz
    dest: /var/lib/aide/aide.db.gz
    backup: true
    remote_src: true
  when:
  - '"kernel" in ansible_facts.packages'
  - (aide_database_stat.stat.exists is defined and aide_database_stat.stat.exists)
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Configure AIDE to Verify the Audit Tools   [ref]

The operating system file integrity tool must be configured to protect the integrity of the audit tools.
Rationale:
Protecting the integrity of the tools used for auditing purposes is a critical step toward ensuring the integrity of audit information. Audit information includes all information (e.g., audit records, audit settings, and audit reports) needed to successfully audit information system activity. Audit tools include but are not limited to vendor-provided and open-source audit tools needed to successfully view and manipulate audit information system activity and records. Audit tools include custom queries and report generators. It is not uncommon for attackers to replace the audit tools or inject code into the existing tools to provide the capability to hide or erase system activity from the audit logs. To address this risk, audit tools must be cryptographically signed to provide the capability to identify when the audit tools have been modified, manipulated, or replaced. An example is a checksum hash of the file or files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_aide_check_audit_tools
References:
disaCCI-001496, CCI-001494, CCI-001495, CCI-001493
nistAU-9(3), AU-9(3).1
os-srgSRG-OS-000278-GPOS-00108
cis1.3.3

Rule   Configure Periodic Execution of AIDE   [ref]

At a minimum, AIDE should be configured to run a weekly scan. To implement a daily execution of AIDE at 4:05am using cron, add the following line to /etc/crontab:
05 4 * * * root /usr/sbin/aide --check
To implement a weekly execution of AIDE at 4:05am using cron, add the following line to /etc/crontab:
05 4 * * 0 root /usr/sbin/aide --check
AIDE can be executed periodically through other means; this is merely one example. The usage of cron's special time codes, such as @daily and @weekly is acceptable.
Rationale:
By default, AIDE does not install itself for periodic execution. Periodically running AIDE is necessary to reveal unexpected changes in installed files.

Unauthorized changes to the baseline configuration could make the system vulnerable to various attacks or allow unauthorized access to the operating system. Changes to operating system configurations can have unintended side effects, some of which may be relevant to security.

Detecting such changes and providing an automated response can help avoid unintended, negative consequences that could ultimately affect the security state of the operating system. The operating system's Information Management Officer (IMO)/Information System Security Officer (ISSO) and System Administrators (SAs) must be notified via email and/or monitoring system trap when there is an unauthorized modification of a configuration item.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_aide_periodic_cron_checking
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 5, 7, 8, 9
cjis5.10.1.3
cobit5APO01.06, BAI01.06, BAI02.01, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS04.07, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.02, DSS06.06
disaCCI-002702, CCI-001744, CCI-002699
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 4.1, SR 6.2, SR 7.6
iso27001-2013A.11.2.4, A.12.1.2, A.12.2.1, A.12.4.1, 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, A.14.2.7, A.15.2.1, A.8.2.3
nistSI-7, SI-7(1), CM-6(a)
nist-csfDE.CM-1, DE.CM-7, PR.DS-1, PR.DS-6, PR.DS-8, PR.IP-1, PR.IP-3
pcidssReq-11.5
os-srgSRG-OS-000363-GPOS-00150, SRG-OS-000446-GPOS-00200, SRG-OS-000447-GPOS-00201
anssiR76
cis1.3.2
pcidss411.5.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure AIDE is installed
  package:
    name: '{{ item }}'
    state: present
  with_items:
  - aide
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set cron package name - RedHat
  set_fact:
    cron_pkg_name: cronie
  when:
  - '"kernel" in ansible_facts.packages'
  - ansible_os_family == "RedHat" or ansible_os_family == "Suse"
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set cron package name - Debian
  set_fact:
    cron_pkg_name: cron
  when:
  - '"kernel" in ansible_facts.packages'
  - ansible_os_family == "Debian"
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Install cron
  package:
    name: '{{ cron_pkg_name }}'
    state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Configure Periodic Execution of AIDE
  cron:
    name: run AIDE check
    minute: 5
    hour: 4
    weekday: 0
    user: root
    job: /usr/sbin/aide --check
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - PCI-DSSv4-11.5.2
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
Group   System Cryptographic Policies   Group contains 2 rules
[ref]   Linux has the capability to centrally configure cryptographic polices. The command update-crypto-policies is used to set the policy applicable for the various cryptographic back-ends, such as SSL/TLS libraries. The configured cryptographic policies will be the default policy used by these backends unless the application user configures them otherwise. When the system has been configured to use the centralized cryptographic policies, the administrator is assured that any application that utilizes the supported backends will follow a policy that adheres to the configured profile. Currently the supported backends are:
  • GnuTLS library
  • OpenSSL library
  • NSS library
  • OpenJDK
  • Libkrb5
  • BIND
  • OpenSSH
Applications and languages which rely on any of these backends will follow the system policies as well. Examples are apache httpd, nginx, php, and others.

Rule   Configure System Cryptography Policy   [ref]

To configure the system cryptography policy to use ciphers only from the DEFAULT policy, run the following command:
$ sudo update-crypto-policies --set DEFAULT
         
The rule checks if settings for selected crypto policy are configured as expected. Configuration files in the /etc/crypto-policies/back-ends are either symlinks to correct files provided by Crypto-policies package or they are regular files in case crypto policy customizations are applied. Crypto policies may be customized by crypto policy modules, in which case it is delimited from the base policy using a colon.
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:
Centralized cryptographic policies simplify applying secure ciphers across an operating system and the applications that run on that operating system. Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_configure_crypto_policy
References:
disaCCI-000068, CCI-003123, CCI-002450, CCI-000877, CCI-002418, CCI-001453, CCI-002890
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.312(e)(1), 164.312(e)(2)(ii)
ism1446
nerc-cipCIP-003-8 R4.2, CIP-007-3 R5.1, CIP-007-3 R7.1
nistAC-17(a), AC-17(2), CM-6(a), MA-4(6), SC-13, SC-12(2), SC-12(3)
osppFCS_COP.1(1), FCS_COP.1(2), FCS_COP.1(3), FCS_COP.1(4), FCS_CKM.1, FCS_CKM.2, FCS_TLSC_EXT.1
os-srgSRG-OS-000396-GPOS-00176, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174
cis1.9
pcidss42.2.7, 2.2


var_system_crypto_policy='DEFAULT'


stderr_of_call=$(update-crypto-policies --set ${var_system_crypto_policy} 2>&1 > /dev/null)
rc=$?

if test "$rc" = 127; then
	echo "$stderr_of_call" >&2
	echo "Make sure that the script is installed on the remediated system." >&2
	echo "See output of the 'dnf provides update-crypto-policies' command" >&2
	echo "to see what package to (re)install" >&2

	false  # end with an error code
elif test "$rc" != 0; then
	echo "Error invoking the update-crypto-policies script: $stderr_of_call" >&2
	false  # end with an error code
fi

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

- name: Configure System Cryptography Policy
  lineinfile:
    path: /etc/crypto-policies/config
    regexp: ^(?!#)(\S+)$
    line: '{{ var_system_crypto_policy }}'
    create: true
  tags:
  - 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
  - PCI-DSSv4-2.2.7
  - configure_crypto_policy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy

- name: Verify that Crypto Policy is Set (runtime)
  command: /usr/bin/update-crypto-policies --set {{ var_system_crypto_policy }}
  tags:
  - 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
  - PCI-DSSv4-2.2.7
  - configure_crypto_policy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy

Rule   Configure SSH to use System Crypto Policy   [ref]

Crypto Policies provide a centralized control over crypto algorithms usage of many packages. SSH is supported by crypto policy, but the SSH configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, ensure that the CRYPTO_POLICY variable is either commented or not set at all in the /etc/sysconfig/sshd.
Rationale:
Overriding the system crypto policy makes the behavior of the SSH service violate expectations, and makes system configuration more fragmented.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_configure_ssh_crypto_policy
References:
disaCCI-001453
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.312(e)(1), 164.312(e)(2)(ii)
nerc-cipCIP-003-8 R4.2, CIP-007-3 R5.1, CIP-007-3 R7.1
nistAC-17(a), AC-17(2), CM-6(a), MA-4(6), SC-13
osppFCS_SSH_EXT.1, FCS_SSHS_EXT.1, FCS_SSHC_EXT.1
pcidssReq-2.2
os-srgSRG-OS-000250-GPOS-00093
cis4.2.14
pcidss42.2.7, 2.2


SSH_CONF="/etc/sysconfig/sshd"

sed -i "/^\s*CRYPTO_POLICY.*$/Id" $SSH_CONF

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Configure SSH to use System Crypto Policy
  lineinfile:
    dest: /etc/sysconfig/sshd
    state: absent
    regexp: (?i)^\s*CRYPTO_POLICY.*$
  tags:
  - 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-13
  - PCI-DSS-Req-2.2
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.7
  - configure_ssh_crypto_policy
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
Group   Disk Partitioning   Group contains 2 rules
[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.

Rule   Ensure /dev/shm is configured   [ref]

The /dev/shm is a traditional shared memory concept. One program will create a memory portion, which other processes (if permitted) can access. If /dev/shm is not configured, tmpfs will be mounted to /dev/shm by systemd.
Warning:  This rule does not have a remedation. It is expected that this will be managed by systemd and will be a tmpfs partition.
Rationale:
Any user can upload and execute files inside the /dev/shm similar to the /tmp partition. Configuring /dev/shm allows an administrator to set the noexec option on the mount, making /dev/shm useless for an attacker to install executable code. It would also prevent an attacker from establishing a hardlink to a system setuid program and wait for it to be updated. Once the program was updated, the hardlink would be broken and the attacker would have his own copy of the program. If the program happened to have a security vulnerability, the attacker could continue to exploit the known flaw.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_partition_for_dev_shm
References:
cis1.1.8.1

Rule   Ensure /tmp Located On Separate Partition   [ref]

The /tmp directory is a world-writable directory used for temporary file storage. Ensure it has its own partition or logical volume at installation time, or migrate it using LVM.
Rationale:
The /tmp partition is used as temporary storage by many programs. Placing /tmp in its own partition enables the setting of more restrictive mount options, which can help protect programs which use it.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_partition_for_tmp
References:
cis-csc12, 15, 8
cobit5APO13.01, DSS05.02
disaCCI-000366
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-6(a), SC-5(2)
nist-csfPR.PT-4
os-srgSRG-OS-000480-GPOS-00227
cis1.1.2.1
Group   Sudo   Group contains 4 rules
[ref]   Sudo, which stands for "su 'do'", provides the ability to delegate authority to certain users, groups of users, or system administrators. When configured for system users and/or groups, Sudo can allow a user or group to execute privileged commands that normally only root is allowed to execute.

For more information on Sudo and addition Sudo configuration options, see https://www.sudo.ws.

Rule   Install sudo Package   [ref]

The sudo package can be installed with the following command:
$ sudo dnf install sudo
Rationale:
sudo is a program designed to allow a system administrator to give limited root privileges to users and log root activity. The basic philosophy is to give as few privileges as possible but still allow system users to get their work done.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_sudo_installed
References:
disaCCI-002235
ism1382, 1384, 1386
nistCM-6(a)
osppFMT_MOF_EXT.1
os-srgSRG-OS-000324-GPOS-00125
anssiR33
cis4.3.1
pcidss42.2.6, 2.2


[[packages]]
name = "sudo"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_sudo_installed

- name: Ensure sudo is installed
  package:
    name: sudo
    state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_sudo_installed

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

class install_sudo {
  package { 'sudo':
    ensure => 'installed',
  }
}

Rule   Ensure Only Users Logged In To Real tty Can Execute Sudo - sudo use_pty   [ref]

The sudo use_pty tag, when specified, will only execute sudo commands from users logged in to a real tty. This should be enabled by making sure that the use_pty tag exists in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/.
Rationale:
Requiring that sudo commands be run in a pseudo-terminal can prevent an attacker from retaining access to the user's terminal after the main program has finished executing.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sudo_add_use_pty
References:
pcidssReq-10.2.5
anssiR39
cis4.3.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q sudo; then

if /usr/sbin/visudo -qcf /etc/sudoers; then
    cp /etc/sudoers /etc/sudoers.bak
    if ! grep -P '^[\s]*Defaults[\s]*\buse_pty\b.*$' /etc/sudoers; then
        # sudoers file doesn't define Option use_pty
        echo "Defaults use_pty" >> /etc/sudoers
    fi
    
    # Check validity of sudoers and cleanup bak
    if /usr/sbin/visudo -qcf /etc/sudoers; then
        rm -f /etc/sudoers.bak
    else
        echo "Fail to validate remediated /etc/sudoers, reverting to original file."
        mv /etc/sudoers.bak /etc/sudoers
        false
    fi
else
    echo "Skipping remediation, /etc/sudoers failed to validate"
    false
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_add_use_pty

- name: Ensure use_pty is enabled in /etc/sudoers
  lineinfile:
    path: /etc/sudoers
    regexp: ^[\s]*Defaults.*\buse_pty\b.*$
    line: Defaults use_pty
    validate: /usr/sbin/visudo -cf %s
  when: '"sudo" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_add_use_pty

Rule   Ensure Sudo Logfile Exists - sudo logfile   [ref]

A custom log sudo file can be configured with the 'logfile' tag. This rule configures a sudo custom logfile at the default location suggested by CIS, which uses /var/log/sudo.log.
Rationale:
A sudo log file simplifies auditing of sudo commands.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_sudo_custom_logfile
References:
pcidssReq-10.2.5
cis4.3.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q sudo; then

var_sudo_logfile='/var/log/sudo.log'


if /usr/sbin/visudo -qcf /etc/sudoers; then
    cp /etc/sudoers /etc/sudoers.bak
    if ! grep -P '^[\s]*Defaults[\s]*\blogfile\s*=\s*(?:"?([^",\s]+)"?)\b.*$' /etc/sudoers; then
        # sudoers file doesn't define Option logfile
        echo "Defaults logfile=${var_sudo_logfile}" >> /etc/sudoers
    else
        # sudoers file defines Option logfile, remediate if appropriate value is not set
        if ! grep -P "^[\s]*Defaults.*\blogfile=${var_sudo_logfile}\b.*$" /etc/sudoers; then
            
            escaped_variable=${var_sudo_logfile//$'/'/$'\/'}
            sed -Ei "s/(^[\s]*Defaults.*\blogfile=)[-]?.+(\b.*$)/\1$escaped_variable\2/" /etc/sudoers
        fi
    fi
    
    # Check validity of sudoers and cleanup bak
    if /usr/sbin/visudo -qcf /etc/sudoers; then
        rm -f /etc/sudoers.bak
    else
        echo "Fail to validate remediated /etc/sudoers, reverting to original file."
        mv /etc/sudoers.bak /etc/sudoers
        false
    fi
else
    echo "Skipping remediation, /etc/sudoers failed to validate"
    false
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_custom_logfile
- name: XCCDF Value var_sudo_logfile # promote to variable
  set_fact:
    var_sudo_logfile: !!str /var/log/sudo.log
  tags:
    - always

- name: Ensure logfile is enabled with the appropriate value in /etc/sudoers
  lineinfile:
    path: /etc/sudoers
    regexp: ^[\s]*Defaults\s(.*)\blogfile=[-]?.+\b(.*)$
    line: Defaults \1logfile={{ var_sudo_logfile }}\2
    validate: /usr/sbin/visudo -cf %s
    backrefs: true
  register: edit_sudoers_logfile_option
  when: '"sudo" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_custom_logfile

- name: Enable logfile option with appropriate value in /etc/sudoers
  lineinfile:
    path: /etc/sudoers
    line: Defaults logfile={{ var_sudo_logfile }}
    validate: /usr/sbin/visudo -cf %s
  when:
  - '"sudo" in ansible_facts.packages'
  - edit_sudoers_logfile_option is defined and not edit_sudoers_logfile_option.changed
  tags:
  - PCI-DSS-Req-10.2.5
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_custom_logfile

Rule   Require Re-Authentication When Using the sudo Command   [ref]

The sudo timestamp_timeout tag sets the amount of time sudo password prompt waits. The default timestamp_timeout value is 5 minutes. The timestamp_timeout should be configured by making sure that the timestamp_timeout tag exists in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/. If the value is set to an integer less than 0, the user's time stamp will not expire and the user will not have to re-authenticate for privileged actions until the user's session is terminated.
Rationale:
Without re-authentication, users may access resources or perform tasks for which they do not have authorization.

When operating systems provide the capability to escalate a functional capability, it is critical that the user re-authenticate.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sudo_require_reauthentication
References:
disaCCI-004895
nistIA-11
os-srgSRG-OS-000373-GPOS-00156, SRG-OS-000373-GPOS-00157, SRG-OS-000373-GPOS-00158
cis4.3.4, 4.3.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q sudo; then

var_sudo_timestamp_timeout='5'


if grep -Px '^[\s]*Defaults.*timestamp_timeout[\s]*=.*' /etc/sudoers.d/*; then
    find /etc/sudoers.d/ -type f -exec sed -Ei "/^[[:blank:]]*Defaults.*timestamp_timeout[[:blank:]]*=.*/d" {} \;
fi

if /usr/sbin/visudo -qcf /etc/sudoers; then
    cp /etc/sudoers /etc/sudoers.bak
    if ! grep -P '^[\s]*Defaults.*timestamp_timeout[\s]*=[\s]*[-]?\w+.*$' /etc/sudoers; then
        # sudoers file doesn't define Option timestamp_timeout
        echo "Defaults timestamp_timeout=${var_sudo_timestamp_timeout}" >> /etc/sudoers
    else
        # sudoers file defines Option timestamp_timeout, remediate wrong values if present
        if grep -qP "^[\s]*Defaults\s.*\btimestamp_timeout[\s]*=[\s]*(?!${var_sudo_timestamp_timeout}\b)[-]?\w+\b.*$" /etc/sudoers; then
            sed -Ei "s/(^[[:blank:]]*Defaults.*timestamp_timeout[[:blank:]]*=)[[:blank:]]*[-]?\w+(.*$)/\1${var_sudo_timestamp_timeout}\2/" /etc/sudoers
        fi
    fi
    
    # Check validity of sudoers and cleanup bak
    if /usr/sbin/visudo -qcf /etc/sudoers; then
        rm -f /etc/sudoers.bak
    else
        echo "Fail to validate remediated /etc/sudoers, reverting to original file."
        mv /etc/sudoers.bak /etc/sudoers
        false
    fi
else
    echo "Skipping remediation, /etc/sudoers failed to validate"
    false
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-IA-11
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_require_reauthentication
- name: XCCDF Value var_sudo_timestamp_timeout # promote to variable
  set_fact:
    var_sudo_timestamp_timeout: !!str 5
  tags:
    - always

- name: Require Re-Authentication When Using the sudo Command - Find /etc/sudoers.d/*
    files containing 'Defaults timestamp_timeout'
  ansible.builtin.find:
    path: /etc/sudoers.d
    patterns: '*'
    contains: ^[\s]*Defaults\s.*\btimestamp_timeout[\s]*=.*
  register: sudoers_d_defaults_timestamp_timeout
  when: '"sudo" in ansible_facts.packages'
  tags:
  - NIST-800-53-IA-11
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_require_reauthentication

- name: Require Re-Authentication When Using the sudo Command - Remove 'Defaults timestamp_timeout'
    from /etc/sudoers.d/* files
  ansible.builtin.lineinfile:
    path: '{{ item.path }}'
    regexp: ^[\s]*Defaults\s.*\btimestamp_timeout[\s]*=.*
    state: absent
  with_items: '{{ sudoers_d_defaults_timestamp_timeout.files }}'
  when: '"sudo" in ansible_facts.packages'
  tags:
  - NIST-800-53-IA-11
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_require_reauthentication

- name: Require Re-Authentication When Using the sudo Command - Ensure timestamp_timeout
    has the appropriate value in /etc/sudoers
  ansible.builtin.lineinfile:
    path: /etc/sudoers
    regexp: ^[\s]*Defaults\s(.*)\btimestamp_timeout[\s]*=[\s]*[-]?\w+\b(.*)$
    line: Defaults \1timestamp_timeout={{ var_sudo_timestamp_timeout }}\2
    validate: /usr/sbin/visudo -cf %s
    backrefs: true
  register: edit_sudoers_timestamp_timeout_option
  when: '"sudo" in ansible_facts.packages'
  tags:
  - NIST-800-53-IA-11
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_require_reauthentication

- name: Require Re-Authentication When Using the sudo Command - Enable timestamp_timeout
    option with correct value in /etc/sudoers
  ansible.builtin.lineinfile:
    path: /etc/sudoers
    line: Defaults timestamp_timeout={{ var_sudo_timestamp_timeout }}
    validate: /usr/sbin/visudo -cf %s
  when:
  - '"sudo" in ansible_facts.packages'
  - |
    edit_sudoers_timestamp_timeout_option is defined and not edit_sudoers_timestamp_timeout_option.changed
  tags:
  - NIST-800-53-IA-11
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_require_reauthentication

- name: Require Re-Authentication When Using the sudo Command - Remove timestamp_timeout
    wrong values in /etc/sudoers
  ansible.builtin.lineinfile:
    path: /etc/sudoers
    regexp: ^[\s]*Defaults\s.*\btimestamp_timeout[\s]*=[\s]*(?!{{ var_sudo_timestamp_timeout
      }}\b)[-]?\w+\b.*$
    state: absent
    validate: /usr/sbin/visudo -cf %s
  when: '"sudo" in ansible_facts.packages'
  tags:
  - NIST-800-53-IA-11
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_require_reauthentication
Group   Updating Software   Group contains 1 rule
[ref]   The dnf 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.

Amazon Linux 2023 systems contain an installed software catalog called the RPM database, which records metadata of installed packages. Consistently using dnf 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 dnf Configuration   [ref]

The gpgcheck option controls whether RPM packages' signatures are always checked prior to installation. To configure dnf to check package signatures before installing them, ensure the following line appears in /etc/dnf/dnf.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
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-003992
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, 6.3

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - 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
  - 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/dnf/dnf.conf
    section: main
    option: gpgcheck
    value: 1
    no_extra_spaces: true
    create: false
  when: '"dnf" in ansible_facts.packages'
  tags:
  - 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
  - PCI-DSSv4-6.3.3
  - configure_strategy
  - ensure_gpgcheck_globally_activated
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
Group   Account and Access Control   Group contains 14 groups and 62 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 Amazon Linux 2023.
Group   Warning Banners for System Accesses   Group contains 12 rules
[ref]   Each system should expose as little information about itself as possible.

System banners, which are typically displayed just before a login prompt, give out information about the service or the host's operating system. This might include the distribution name and the system kernel version, and the particular version of a network service. This information can assist intruders in gaining access to the system as it can reveal whether the system is running vulnerable software. Most network services can be configured to limit what information is displayed.

Many organizations implement security policies that require a system banner provide notice of the system's ownership, provide warning to unauthorized users, and remind authorized users of their consent to monitoring.

Rule   Modify the System Login Banner   [ref]

To configure the system login banner edit /etc/issue. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.


OR:

I've read & consent to terms in IS user agreem't.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_issue
References:
cis-csc1, 12, 15, 16
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.9
disaCCI-001387, CCI-001384, CCI-000048, CCI-001386, CCI-001388, CCI-001385
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)
nist-csfPR.AC-7
os-srgSRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088
cis1.7.2

Rule   Modify the System Login Banner for Remote Connections   [ref]

To configure the system login banner edit /etc/issue.net. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.


OR:

I've read & consent to terms in IS user agreem't.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_issue_net
References:
disaCCI-000048, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388
os-srgSRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088
cis1.7.3

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

remote_login_banner_text='^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$'


# Multiple regexes transform the banner regex into a usable banner
# 0 - Remove anchors around the banner text
remote_login_banner_text=$(echo "$remote_login_banner_text" | sed 's/^\^\(.*\)\$$/\1/g')
# 1 - Keep only the first banners if there are multiple
#    (dod_banners contains the long and short banner)
remote_login_banner_text=$(echo "$remote_login_banner_text" | sed 's/^(\(.*\.\)|.*)$/\1/g')
# 2 - Add spaces ' '. (Transforms regex for "space or newline" into a " ")
remote_login_banner_text=$(echo "$remote_login_banner_text" | sed 's/\[\\s\\n\]+/ /g')
# 3 - Adds newlines. (Transforms "(?:\[\\n\]+|(?:\\n)+)" into "\n")
remote_login_banner_text=$(echo "$remote_login_banner_text" | sed 's/(?:\[\\n\]+|(?:\\\\n)+)/\n/g')
# 4 - Remove any leftover backslash. (From any parethesis in the banner, for example).
remote_login_banner_text=$(echo "$remote_login_banner_text" | sed 's/\\//g')
formatted=$(echo "$remote_login_banner_text" | fold -sw 80)

cat <<EOF >/etc/issue.net
$formatted
EOF

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

Complexity:low
Disruption:medium
Reboot:false
Strategy:unknown
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - banner_etc_issue_net
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy
- name: XCCDF Value remote_login_banner_text # promote to variable
  set_fact:
    remote_login_banner_text: !!str ^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$
  tags:
    - always

- name: Modify the System Login Banner for Remote Connections - ensure correct banner
  copy:
    dest: /etc/issue.net
    content: '{{ remote_login_banner_text | regex_replace("^\^(.*)\$$", "\1") | regex_replace("^\((.*\.)\|.*\)$",
      "\1") | regex_replace("\[\\s\\n\]\+"," ") | regex_replace("\(\?:\[\\n\]\+\|\(\?:\\\\n\)\+\)",
      "\n") | regex_replace("\\", "") | wordwrap() }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - banner_etc_issue_net
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

Rule   Modify the System Message of the Day Banner   [ref]

To configure the system message banner edit /etc/motd. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.


OR:

I've read & consent to terms in IS user agreem't.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_motd
References:
cis1.7.1

Rule   Verify Group Ownership of System Login Banner   [ref]

To properly set the group owner of /etc/issue, run the command:
$ sudo chgrp root /etc/issue
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper group ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_issue
References:
cis1.7.5

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/issue

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/issue
  stat:
    path: /etc/issue
  register: file_exists
  tags:
  - configure_strategy
  - file_groupowner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/issue
  file:
    path: /etc/issue
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Ownership of System Login Banner for Remote Connections   [ref]

To properly set the group owner of /etc/issue.net, run the command:
$ sudo chgrp root /etc/issue.net
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper group ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_issue_net
References:
cis1.7.6
pcidss41.2.8, 1.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/issue.net

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/issue.net
  stat:
    path: /etc/issue.net
  register: file_exists
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.8
  - configure_strategy
  - file_groupowner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/issue.net
  file:
    path: /etc/issue.net
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.8
  - configure_strategy
  - file_groupowner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Ownership of Message of the Day Banner   [ref]

To properly set the group owner of /etc/motd, run the command:
$ sudo chgrp root /etc/motd
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper group ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_motd
References:
cis1.7.4

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/motd

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/motd
  stat:
    path: /etc/motd
  register: file_exists
  tags:
  - configure_strategy
  - file_groupowner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/motd
  file:
    path: /etc/motd
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify ownership of System Login Banner   [ref]

To properly set the owner of /etc/issue, run the command:
$ sudo chown root /etc/issue 
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_issue
References:
cis1.7.5

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/issue

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/issue
  stat:
    path: /etc/issue
  register: file_exists
  tags:
  - configure_strategy
  - file_owner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/issue
  file:
    path: /etc/issue
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify ownership of System Login Banner for Remote Connections   [ref]

To properly set the owner of /etc/issue.net, run the command:
$ sudo chown root /etc/issue.net 
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_issue_net
References:
cis1.7.6
pcidss41.2.8, 1.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/issue.net

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/issue.net
  stat:
    path: /etc/issue.net
  register: file_exists
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.8
  - configure_strategy
  - file_owner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/issue.net
  file:
    path: /etc/issue.net
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.8
  - configure_strategy
  - file_owner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify ownership of Message of the Day Banner   [ref]

To properly set the owner of /etc/motd, run the command:
$ sudo chown root /etc/motd 
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_motd
References:
cis1.7.4

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/motd

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/motd
  stat:
    path: /etc/motd
  register: file_exists
  tags:
  - configure_strategy
  - file_owner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/motd
  file:
    path: /etc/motd
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify permissions on System Login Banner   [ref]

To properly set the permissions of /etc/issue, run the command:
$ sudo chmod 0644 /etc/issue
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper permissions will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_issue
References:
cis1.7.5

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




chmod u-xs,g-xws,o-xwt /etc/issue

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/issue
  stat:
    path: /etc/issue
  register: file_exists
  tags:
  - configure_strategy
  - file_permissions_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/issue
  file:
    path: /etc/issue
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify permissions on System Login Banner for Remote Connections   [ref]

To properly set the permissions of /etc/issue.net, run the command:
$ sudo chmod 0644 /etc/issue.net
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper permissions will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_issue_net
References:
cis1.7.6
pcidss41.2.8, 1.2

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




chmod u-xs,g-xws,o-xwt /etc/issue.net

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/issue.net
  stat:
    path: /etc/issue.net
  register: file_exists
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.8
  - configure_strategy
  - file_permissions_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/issue.net
  file:
    path: /etc/issue.net
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.8
  - configure_strategy
  - file_permissions_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify permissions on Message of the Day Banner   [ref]

To properly set the permissions of /etc/motd, run the command:
$ sudo chmod 0644 /etc/motd
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper permissions will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_motd
References:
cis1.7.4

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




chmod u-xs,g-xws,o-xwt /etc/motd

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/motd
  stat:
    path: /etc/motd
  register: file_exists
  tags:
  - configure_strategy
  - file_permissions_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/motd
  file:
    path: /etc/motd
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
Group   Protect Accounts by Configuring PAM   Group contains 4 groups and 12 rules
[ref]   PAM, or Pluggable Authentication Modules, is a system which implements modular authentication for Linux programs. PAM provides a flexible and configurable architecture for authentication, and it should be configured to minimize exposure to unnecessary risk. This section contains guidance on how to accomplish that.

PAM is implemented as a set of shared objects which are loaded and invoked whenever an application wishes to authenticate a user. Typically, the application must be running as root in order to take advantage of PAM, because PAM's modules often need to be able to access sensitive stores of account information, such as /etc/shadow. Traditional privileged network listeners (e.g. sshd) or SUID programs (e.g. sudo) already meet this requirement. An SUID root application, userhelper, is provided so that programs which are not SUID or privileged themselves can still take advantage of PAM.

PAM looks in the directory /etc/pam.d for application-specific configuration information. For instance, if the program login attempts to authenticate a user, then PAM's libraries follow the instructions in the file /etc/pam.d/login to determine what actions should be taken.

One very important file in /etc/pam.d is /etc/pam.d/system-auth. This file, which is included by many other PAM configuration files, defines 'default' system authentication measures. Modifying this file is a good way to make far-reaching authentication changes, for instance when implementing a centralized authentication service.
Warning:  Be careful when making changes to PAM's configuration files. The syntax for these files is complex, and modifications can have unexpected consequences. The default configurations shipped with applications should be sufficient for most users.
Warning:  Running authconfig or system-config-authentication will re-write the PAM configuration files, destroying any manually made changes and replacing them with a series of system defaults. One reference to the configuration file syntax can be found at https://fossies.org/linux/Linux-PAM-docs/doc/sag/Linux-PAM_SAG.pdf.
Group   Set Lockouts for Failed Password Attempts   Group contains 6 rules
[ref]   The pam_faillock PAM module provides the capability to lock out user accounts after a number of failed login attempts. Its documentation is available in /usr/share/doc/pam-VERSION/txts/README.pam_faillock.

Warning:  Locking out user accounts presents the risk of a denial-of-service attack. The lockout policy must weigh whether the risk of such a denial-of-service attack outweighs the benefits of thwarting password guessing attacks.

Rule   Limit Password Reuse: password-auth   [ref]

Do not allow users to reuse recent passwords. This can be accomplished by using the remember option for the pam_pwhistory PAM module.

On systems with newer versions of authselect, the pam_pwhistory PAM module can be enabled via authselect feature:
authselect enable-feature with-pwhistory
Otherwise, it should be enabled using an authselect custom profile.

Newer systems also have the /etc/security/pwhistory.conf file for setting pam_pwhistory module options. This file should be used whenever available. Otherwise, the pam_pwhistory module options can be set in PAM files.

The value for remember option must be equal or greater than 5
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.
Warning:  Newer versions of authselect contain an authselect feature to easily and properly enable pam_pwhistory.so module. If this feature is not yet available in your system, an authselect custom profile must be used to avoid integrity issues in PAM files. If a custom profile was created and used in the system before this authselect feature was available, the new feature can't be used with this custom profile and the remediation will fail. In this case, the custom profile should be recreated or manually updated.
Rationale:
Preventing re-use of previous passwords helps ensure that a compromised password is not re-used by a user.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_pwhistory_remember_password_auth
References:
cis-csc1, 12, 15, 16, 5
cjis5.6.2.1.1
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.5.8
disaCCI-000200
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
nistIA-5(f), IA-5(1)(e)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
pcidssReq-8.2.5
os-srgSRG-OS-000077-GPOS-00045
cis4.5.3
pcidss48.3.7, 8.3

Rule   Limit Password Reuse: system-auth   [ref]

Do not allow users to reuse recent passwords. This can be accomplished by using the remember option for the pam_pwhistory PAM module.

On systems with newer versions of authselect, the pam_pwhistory PAM module can be enabled via authselect feature:
authselect enable-feature with-pwhistory
Otherwise, it should be enabled using an authselect custom profile.

Newer systems also have the /etc/security/pwhistory.conf file for setting pam_pwhistory module options. This file should be used whenever available. Otherwise, the pam_pwhistory module options can be set in PAM files.

The value for remember option must be equal or greater than 5
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.
Warning:  Newer versions of authselect contain an authselect feature to easily and properly enable pam_pwhistory.so module. If this feature is not yet available in your system, an authselect custom profile must be used to avoid integrity issues in PAM files.
Rationale:
Preventing re-use of previous passwords helps ensure that a compromised password is not re-used by a user.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_pwhistory_remember_system_auth
References:
cis-csc1, 12, 15, 16, 5
cjis5.6.2.1.1
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.5.8
disaCCI-000200
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
nistIA-5(f), IA-5(1)(e)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
pcidssReq-8.2.5
os-srgSRG-OS-000077-GPOS-00045
cis4.5.3
pcidss48.3.7, 8.3

Rule   Lock Accounts After Failed Password Attempts   [ref]

This rule configures the system to lock out accounts after a number of incorrect login attempts using pam_faillock.so. pam_faillock.so module requires multiple entries in pam files. These entries must be carefully defined to work as expected. Ensure that the file /etc/security/faillock.conf contains the following entry: deny = <count> Where count should be less than or equal to 3 and greater than 0. In order to avoid errors when manually editing these files, it is recommended to use the appropriate tools, such as authselect or authconfig, depending on the OS version.
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. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.
Rationale:
By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, also known as brute-forcing, is reduced. Limits are imposed by locking the account.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny
References:
cis-csc1, 12, 15, 16
cjis5.5.3
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.8
disaCCI-000044, CCI-002238
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
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
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
nistCM-6(a), AC-7(a)
nist-csfPR.AC-7
osppFIA_AFL.1
pcidssReq-8.1.6
os-srgSRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005
anssiR31
cis4.5.2
pcidss48.3.4, 8.3

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

var_accounts_passwords_pam_faillock_deny='3'


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 with-faillock

authselect apply-changes -b
else
    
AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
for pam_file in "${AUTH_FILES[@]}"
do
    if ! grep -qE '^\s*auth\s+required\s+pam_faillock\.so\s+(preauth silent|authfail).*$' "$pam_file" ; then
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix\.so.*/i auth        required      pam_faillock.so preauth silent' "$pam_file"
        sed -i --follow-symlinks '/^auth.*required.*pam_deny\.so.*/i auth        required      pam_faillock.so authfail' "$pam_file"
        sed -i --follow-symlinks '/^account.*required.*pam_unix\.so.*/i account     required      pam_faillock.so' "$pam_file"
    fi
    sed -Ei 's/(auth.*)(\[default=die\])(.*pam_faillock\.so)/\1required     \3/g' "$pam_file"
done

fi

AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
SKIP_FAILLOCK_CHECK=false

FAILLOCK_CONF="/etc/security/faillock.conf"
if [ -f $FAILLOCK_CONF ] || [ "$SKIP_FAILLOCK_CHECK" = "true" ]; then
    regex="^\s*deny\s*="
    line="deny = $var_accounts_passwords_pam_faillock_deny"
    if ! grep -q $regex $FAILLOCK_CONF; then
        echo $line >> $FAILLOCK_CONF
    else
        sed -i --follow-symlinks 's|^\s*\(deny\s*=\s*\)\(\S\+\)|\1'"$var_accounts_passwords_pam_faillock_deny"'|g' $FAILLOCK_CONF
    fi
    
    for pam_file in "${AUTH_FILES[@]}"
    do
        if [ -e "$pam_file" ] ; then
            PAM_FILE_PATH="$pam_file"
            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

                CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
                # If not already in use, a custom profile is created preserving the enabled features.
                if [[ ! $CURRENT_PROFILE == custom/* ]]; then
                    ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
                    authselect create-profile hardening -b $CURRENT_PROFILE
                    CURRENT_PROFILE="custom/hardening"
                    
                    authselect apply-changes -b --backup=before-hardening-custom-profile
                    authselect select $CURRENT_PROFILE
                    for feature in $ENABLED_FEATURES; do
                        authselect enable-feature $feature;
                    done
                    
                    authselect apply-changes -b --backup=after-hardening-custom-profile
                fi
                PAM_FILE_NAME=$(basename "$pam_file")
                PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

                authselect apply-changes -b
            fi
            
        if grep -qP "^\s*auth\s.*\bpam_faillock.so\s.*\bdeny\b" "$PAM_FILE_PATH"; then
            sed -i -E --follow-symlinks "s/(.*auth.*pam_faillock.so.*)\bdeny\b=?[[:alnum:]]*(.*)/\1\2/g" "$PAM_FILE_PATH"
        fi
            if [ -f /usr/bin/authselect ]; then
                
                authselect apply-changes -b
            fi
        else
            echo "$pam_file was not found" >&2
        fi
    done
    
else
    for pam_file in "${AUTH_FILES[@]}"
    do
        if ! grep -qE '^\s*auth.*pam_faillock\.so (preauth|authfail).*deny' "$pam_file"; then
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock\.so.*preauth.*silent.*/ s/$/ deny='"$var_accounts_passwords_pam_faillock_deny"'/' "$pam_file"
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock\.so.*authfail.*/ s/$/ deny='"$var_accounts_passwords_pam_faillock_deny"'/' "$pam_file"
        else
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock\.so.*preauth.*silent.*\)\('"deny"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_deny"'\3/' "$pam_file"
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock\.so.*authfail.*\)\('"deny"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_deny"'\3/' "$pam_file"
        fi
    done
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Check if system relies on authselect
    tool
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Remediation where authselect
    tool is present
  block:

  - name: Lock Accounts After Failed Password Attempts - Check integrity of authselect
      current profile
    ansible.builtin.command:
      cmd: authselect check
    register: result_authselect_check_cmd
    changed_when: false
    failed_when: false

  - name: Lock Accounts After Failed Password Attempts - 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: Lock Accounts After Failed Password Attempts - 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: Lock Accounts After Failed Password Attempts - Ensure "with-faillock" feature
      is enabled using authselect tool
    ansible.builtin.command:
      cmd: authselect enable-feature with-faillock
    register: result_authselect_enable_feature_cmd
    when:
    - result_authselect_check_cmd is success
    - result_authselect_features.stdout is not search("with-faillock")

  - name: Lock Accounts After Failed Password Attempts - 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:
  - '"pam" in ansible_facts.packages'
  - result_authselect_present.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Remediation where authselect
    tool is not present
  block:

  - name: Lock Accounts After Failed Password Attempts - Check if pam_faillock.so
      is already enabled
    ansible.builtin.lineinfile:
      path: /etc/pam.d/system-auth
      regexp: .*auth.*pam_faillock\.so (preauth|authfail)
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_faillock_is_enabled

  - name: Lock Accounts After Failed Password Attempts - Enable pam_faillock.so preauth
      editing PAM files
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      line: auth        required      pam_faillock.so preauth
      insertbefore: ^auth.*sufficient.*pam_unix\.so.*
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_is_enabled.found == 0

  - name: Lock Accounts After Failed Password Attempts - Enable pam_faillock.so authfail
      editing PAM files
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      line: auth        required      pam_faillock.so authfail
      insertbefore: ^auth.*required.*pam_deny\.so.*
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_is_enabled.found == 0

  - name: Lock Accounts After Failed Password Attempts - Enable pam_faillock.so account
      section editing PAM files
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      line: account     required      pam_faillock.so
      insertbefore: ^account.*required.*pam_unix\.so.*
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_is_enabled.found == 0
  when:
  - '"pam" in ansible_facts.packages'
  - not result_authselect_present.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_accounts_passwords_pam_faillock_deny # promote to variable
  set_fact:
    var_accounts_passwords_pam_faillock_deny: !!str 3
  tags:
    - always

- name: Lock Accounts After Failed Password Attempts - Check the presence of /etc/security/faillock.conf
    file
  ansible.builtin.stat:
    path: /etc/security/faillock.conf
  register: result_faillock_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Ensure the pam_faillock.so
    deny parameter in /etc/security/faillock.conf
  ansible.builtin.lineinfile:
    path: /etc/security/faillock.conf
    regexp: ^\s*deny\s*=
    line: deny = {{ var_accounts_passwords_pam_faillock_deny }}
    state: present
  when:
  - '"pam" in ansible_facts.packages'
  - result_faillock_conf_check.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Ensure the pam_faillock.so
    deny parameter not in PAM files
  block:

  - name: Lock Accounts After Failed Password Attempts - Check if /etc/pam.d/system-auth
      file is present
    ansible.builtin.stat:
      path: /etc/pam.d/system-auth
    register: result_pam_file_present

  - name: Lock Accounts After Failed Password Attempts - Check the proper remediation
      for the system
    block:

    - name: Lock Accounts After Failed Password Attempts - Define the PAM file to
        be edited as a local fact
      ansible.builtin.set_fact:
        pam_file_path: /etc/pam.d/system-auth

    - name: Lock Accounts After Failed Password Attempts - Check if system relies
        on authselect tool
      ansible.builtin.stat:
        path: /usr/bin/authselect
      register: result_authselect_present

    - name: Lock Accounts After Failed Password Attempts - Ensure authselect custom
        profile is used if authselect is present
      block:

      - name: Lock Accounts After Failed Password Attempts - Check integrity of authselect
          current profile
        ansible.builtin.command:
          cmd: authselect check
        register: result_authselect_check_cmd
        changed_when: false
        failed_when: false

      - name: Lock Accounts After Failed Password Attempts - 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: Lock Accounts After Failed Password Attempts - Get authselect current
          profile
        ansible.builtin.shell:
          cmd: authselect current -r | awk '{ print $1 }'
        register: result_authselect_profile
        changed_when: false
        when:
        - result_authselect_check_cmd is success

      - name: Lock Accounts After Failed Password Attempts - Define the current authselect
          profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Define the new authselect
          custom profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: custom/hardening
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is not match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Get authselect current
          features to also enable them in the custom profile
        ansible.builtin.shell:
          cmd: authselect current | tail -n+3 | awk '{ print $2 }'
        register: result_authselect_features
        changed_when: false
        when:
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Check if any custom profile
          with the same name was already created
        ansible.builtin.stat:
          path: /etc/authselect/{{ authselect_custom_profile }}
        register: result_authselect_custom_profile_present
        changed_when: false
        when:
        - authselect_current_profile is not match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Create an authselect
          custom profile based on the current profile
        ansible.builtin.command:
          cmd: authselect create-profile hardening -b {{ authselect_current_profile
            }}
        when:
        - result_authselect_check_cmd is success
        - authselect_current_profile is not match("custom/")
        - not result_authselect_custom_profile_present.stat.exists

      - name: Lock Accounts After Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Lock Accounts After Failed Password Attempts - Ensure the authselect
          custom profile is selected
        ansible.builtin.command:
          cmd: authselect select {{ authselect_custom_profile }}
        register: result_pam_authselect_select_profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Lock Accounts After Failed Password Attempts - Restore the authselect
          features in the custom profile
        ansible.builtin.command:
          cmd: authselect enable-feature {{ item }}
        loop: '{{ result_authselect_features.stdout_lines }}'
        register: result_pam_authselect_restore_features
        when:
        - result_authselect_profile is not skipped
        - result_authselect_features is not skipped
        - result_pam_authselect_select_profile is not skipped

      - name: Lock Accounts After Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - result_pam_authselect_restore_features is not skipped

      - name: Lock Accounts After Failed Password Attempts - Change the PAM file to
          be edited according to the custom authselect profile
        ansible.builtin.set_fact:
          pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
            | basename }}
      when:
      - result_authselect_present.stat.exists

    - name: Lock Accounts After Failed Password Attempts - Define a fact for control
        already filtered in case filters are used
      ansible.builtin.set_fact:
        pam_module_control: ''

    - name: Lock Accounts After Failed Password Attempts - Ensure the "deny" option
        from "pam_faillock.so" is not present in {{ pam_file_path }}
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: (.*auth.*pam_faillock.so.*)\bdeny\b=?[0-9a-zA-Z]*(.*)
        replace: \1\2
      register: result_pam_option_removal

    - name: Lock Accounts After Failed Password Attempts - Ensure authselect changes
        are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when:
      - result_authselect_present.stat.exists
      - result_pam_option_removal is changed
    when:
    - result_pam_file_present.stat.exists

  - name: Lock Accounts After Failed Password Attempts - Check if /etc/pam.d/password-auth
      file is present
    ansible.builtin.stat:
      path: /etc/pam.d/password-auth
    register: result_pam_file_present

  - name: Lock Accounts After Failed Password Attempts - Check the proper remediation
      for the system
    block:

    - name: Lock Accounts After Failed Password Attempts - Define the PAM file to
        be edited as a local fact
      ansible.builtin.set_fact:
        pam_file_path: /etc/pam.d/password-auth

    - name: Lock Accounts After Failed Password Attempts - Check if system relies
        on authselect tool
      ansible.builtin.stat:
        path: /usr/bin/authselect
      register: result_authselect_present

    - name: Lock Accounts After Failed Password Attempts - Ensure authselect custom
        profile is used if authselect is present
      block:

      - name: Lock Accounts After Failed Password Attempts - Check integrity of authselect
          current profile
        ansible.builtin.command:
          cmd: authselect check
        register: result_authselect_check_cmd
        changed_when: false
        failed_when: false

      - name: Lock Accounts After Failed Password Attempts - 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: Lock Accounts After Failed Password Attempts - Get authselect current
          profile
        ansible.builtin.shell:
          cmd: authselect current -r | awk '{ print $1 }'
        register: result_authselect_profile
        changed_when: false
        when:
        - result_authselect_check_cmd is success

      - name: Lock Accounts After Failed Password Attempts - Define the current authselect
          profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Define the new authselect
          custom profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: custom/hardening
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is not match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Get authselect current
          features to also enable them in the custom profile
        ansible.builtin.shell:
          cmd: authselect current | tail -n+3 | awk '{ print $2 }'
        register: result_authselect_features
        changed_when: false
        when:
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Check if any custom profile
          with the same name was already created
        ansible.builtin.stat:
          path: /etc/authselect/{{ authselect_custom_profile }}
        register: result_authselect_custom_profile_present
        changed_when: false
        when:
        - authselect_current_profile is not match("custom/")

      - name: Lock Accounts After Failed Password Attempts - Create an authselect
          custom profile based on the current profile
        ansible.builtin.command:
          cmd: authselect create-profile hardening -b {{ authselect_current_profile
            }}
        when:
        - result_authselect_check_cmd is success
        - authselect_current_profile is not match("custom/")
        - not result_authselect_custom_profile_present.stat.exists

      - name: Lock Accounts After Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Lock Accounts After Failed Password Attempts - Ensure the authselect
          custom profile is selected
        ansible.builtin.command:
          cmd: authselect select {{ authselect_custom_profile }}
        register: result_pam_authselect_select_profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Lock Accounts After Failed Password Attempts - Restore the authselect
          features in the custom profile
        ansible.builtin.command:
          cmd: authselect enable-feature {{ item }}
        loop: '{{ result_authselect_features.stdout_lines }}'
        register: result_pam_authselect_restore_features
        when:
        - result_authselect_profile is not skipped
        - result_authselect_features is not skipped
        - result_pam_authselect_select_profile is not skipped

      - name: Lock Accounts After Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - result_pam_authselect_restore_features is not skipped

      - name: Lock Accounts After Failed Password Attempts - Change the PAM file to
          be edited according to the custom authselect profile
        ansible.builtin.set_fact:
          pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
            | basename }}
      when:
      - result_authselect_present.stat.exists

    - name: Lock Accounts After Failed Password Attempts - Define a fact for control
        already filtered in case filters are used
      ansible.builtin.set_fact:
        pam_module_control: ''

    - name: Lock Accounts After Failed Password Attempts - Ensure the "deny" option
        from "pam_faillock.so" is not present in {{ pam_file_path }}
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: (.*auth.*pam_faillock.so.*)\bdeny\b=?[0-9a-zA-Z]*(.*)
        replace: \1\2
      register: result_pam_option_removal

    - name: Lock Accounts After Failed Password Attempts - Ensure authselect changes
        are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when:
      - result_authselect_present.stat.exists
      - result_pam_option_removal is changed
    when:
    - result_pam_file_present.stat.exists
  when:
  - '"pam" in ansible_facts.packages'
  - result_faillock_conf_check.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Lock Accounts After Failed Password Attempts - Ensure the pam_faillock.so
    deny parameter in PAM files
  block:

  - name: Lock Accounts After Failed Password Attempts - Check if pam_faillock.so
      deny parameter is already enabled in pam files
    ansible.builtin.lineinfile:
      path: /etc/pam.d/system-auth
      regexp: .*auth.*pam_faillock\.so (preauth|authfail).*deny
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_faillock_deny_parameter_is_present

  - name: Lock Accounts After Failed Password Attempts - Ensure the inclusion of pam_faillock.so
      preauth deny parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)
      line: \1required\3 deny={{ var_accounts_passwords_pam_faillock_deny }}
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_deny_parameter_is_present.found == 0

  - name: Lock Accounts After Failed Password Attempts - Ensure the inclusion of pam_faillock.so
      authfail deny parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)
      line: \1required\3 deny={{ var_accounts_passwords_pam_faillock_deny }}
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_deny_parameter_is_present.found == 0

  - name: Lock Accounts After Failed Password Attempts - Ensure the desired value
      for pam_faillock.so preauth deny parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)(deny)=[0-9]+(.*)
      line: \1required\3\4={{ var_accounts_passwords_pam_faillock_deny }}\5
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_deny_parameter_is_present.found > 0

  - name: Lock Accounts After Failed Password Attempts - Ensure the desired value
      for pam_faillock.so authfail deny parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)(deny)=[0-9]+(.*)
      line: \1required\3\4={{ var_accounts_passwords_pam_faillock_deny }}\5
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_deny_parameter_is_present.found > 0
  when:
  - '"pam" in ansible_facts.packages'
  - not result_faillock_conf_check.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.6
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Set Lockout Time for Failed Password Attempts   [ref]

This rule configures the system to lock out accounts during a specified time period after a number of incorrect login attempts using pam_faillock.so. Ensure that the file /etc/security/faillock.conf contains the following entry: unlock_time=<interval-in-seconds> where interval-in-seconds is 900 or greater. pam_faillock.so module requires multiple entries in pam files. These entries must be carefully defined to work as expected. In order to avoid any errors when manually editing these files, it is recommended to use the appropriate tools, such as authselect or authconfig, depending on the OS version. If unlock_time is set to 0, manual intervention by an administrator is required to unlock a user. This should be done using the faillock tool.
Warning:  If the system supports the new /etc/security/faillock.conf file but the pam_faillock.so parameters are defined directly in /etc/pam.d/system-auth and /etc/pam.d/password-auth, the remediation will migrate the unlock_time parameter to /etc/security/faillock.conf to ensure compatibility with authselect tool. The parameters deny and fail_interval, if used, also have to be migrated by their respective remediation.
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. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.
Rationale:
By limiting the number of failed logon attempts the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_unlock_time
References:
cis-csc1, 12, 15, 16
cjis5.5.3
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.8
disaCCI-000044, CCI-002238
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
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
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
nistCM-6(a), AC-7(b)
nist-csfPR.AC-7
osppFIA_AFL.1
pcidssReq-8.1.7
os-srgSRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005
anssiR31
cis4.5.2
pcidss48.3.4, 8.3

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

var_accounts_passwords_pam_faillock_unlock_time='900'


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 with-faillock

authselect apply-changes -b
else
    
AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
for pam_file in "${AUTH_FILES[@]}"
do
    if ! grep -qE '^\s*auth\s+required\s+pam_faillock\.so\s+(preauth silent|authfail).*$' "$pam_file" ; then
        sed -i --follow-symlinks '/^auth.*sufficient.*pam_unix\.so.*/i auth        required      pam_faillock.so preauth silent' "$pam_file"
        sed -i --follow-symlinks '/^auth.*required.*pam_deny\.so.*/i auth        required      pam_faillock.so authfail' "$pam_file"
        sed -i --follow-symlinks '/^account.*required.*pam_unix\.so.*/i account     required      pam_faillock.so' "$pam_file"
    fi
    sed -Ei 's/(auth.*)(\[default=die\])(.*pam_faillock\.so)/\1required     \3/g' "$pam_file"
done

fi

AUTH_FILES=("/etc/pam.d/system-auth" "/etc/pam.d/password-auth")
SKIP_FAILLOCK_CHECK=false

FAILLOCK_CONF="/etc/security/faillock.conf"
if [ -f $FAILLOCK_CONF ] || [ "$SKIP_FAILLOCK_CHECK" = "true" ]; then
    regex="^\s*unlock_time\s*="
    line="unlock_time = $var_accounts_passwords_pam_faillock_unlock_time"
    if ! grep -q $regex $FAILLOCK_CONF; then
        echo $line >> $FAILLOCK_CONF
    else
        sed -i --follow-symlinks 's|^\s*\(unlock_time\s*=\s*\)\(\S\+\)|\1'"$var_accounts_passwords_pam_faillock_unlock_time"'|g' $FAILLOCK_CONF
    fi
    
    for pam_file in "${AUTH_FILES[@]}"
    do
        if [ -e "$pam_file" ] ; then
            PAM_FILE_PATH="$pam_file"
            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

                CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
                # If not already in use, a custom profile is created preserving the enabled features.
                if [[ ! $CURRENT_PROFILE == custom/* ]]; then
                    ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
                    authselect create-profile hardening -b $CURRENT_PROFILE
                    CURRENT_PROFILE="custom/hardening"
                    
                    authselect apply-changes -b --backup=before-hardening-custom-profile
                    authselect select $CURRENT_PROFILE
                    for feature in $ENABLED_FEATURES; do
                        authselect enable-feature $feature;
                    done
                    
                    authselect apply-changes -b --backup=after-hardening-custom-profile
                fi
                PAM_FILE_NAME=$(basename "$pam_file")
                PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

                authselect apply-changes -b
            fi
            
        if grep -qP "^\s*auth\s.*\bpam_faillock.so\s.*\bunlock_time\b" "$PAM_FILE_PATH"; then
            sed -i -E --follow-symlinks "s/(.*auth.*pam_faillock.so.*)\bunlock_time\b=?[[:alnum:]]*(.*)/\1\2/g" "$PAM_FILE_PATH"
        fi
            if [ -f /usr/bin/authselect ]; then
                
                authselect apply-changes -b
            fi
        else
            echo "$pam_file was not found" >&2
        fi
    done
    
else
    for pam_file in "${AUTH_FILES[@]}"
    do
        if ! grep -qE '^\s*auth.*pam_faillock\.so (preauth|authfail).*unlock_time' "$pam_file"; then
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock\.so.*preauth.*silent.*/ s/$/ unlock_time='"$var_accounts_passwords_pam_faillock_unlock_time"'/' "$pam_file"
            sed -i --follow-symlinks '/^auth.*required.*pam_faillock\.so.*authfail.*/ s/$/ unlock_time='"$var_accounts_passwords_pam_faillock_unlock_time"'/' "$pam_file"
        else
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock\.so.*preauth.*silent.*\)\('"unlock_time"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_unlock_time"'\3/' "$pam_file"
            sed -i --follow-symlinks 's/\(^auth.*required.*pam_faillock\.so.*authfail.*\)\('"unlock_time"'=\)[0-9]\+\(.*\)/\1\2'"$var_accounts_passwords_pam_faillock_unlock_time"'\3/' "$pam_file"
        fi
    done
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Check if system relies on
    authselect tool
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Remediation where authselect
    tool is present
  block:

  - name: Set Lockout Time for Failed Password Attempts - Check integrity of authselect
      current profile
    ansible.builtin.command:
      cmd: authselect check
    register: result_authselect_check_cmd
    changed_when: false
    failed_when: false

  - name: Set Lockout Time for Failed Password Attempts - 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: Set Lockout Time for Failed Password Attempts - 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: Set Lockout Time for Failed Password Attempts - Ensure "with-faillock" feature
      is enabled using authselect tool
    ansible.builtin.command:
      cmd: authselect enable-feature with-faillock
    register: result_authselect_enable_feature_cmd
    when:
    - result_authselect_check_cmd is success
    - result_authselect_features.stdout is not search("with-faillock")

  - name: Set Lockout Time for Failed Password Attempts - 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:
  - '"pam" in ansible_facts.packages'
  - result_authselect_present.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Remediation where authselect
    tool is not present
  block:

  - name: Set Lockout Time for Failed Password Attempts - Check if pam_faillock.so
      is already enabled
    ansible.builtin.lineinfile:
      path: /etc/pam.d/system-auth
      regexp: .*auth.*pam_faillock\.so (preauth|authfail)
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_faillock_is_enabled

  - name: Set Lockout Time for Failed Password Attempts - Enable pam_faillock.so preauth
      editing PAM files
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      line: auth        required      pam_faillock.so preauth
      insertbefore: ^auth.*sufficient.*pam_unix\.so.*
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_is_enabled.found == 0

  - name: Set Lockout Time for Failed Password Attempts - Enable pam_faillock.so authfail
      editing PAM files
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      line: auth        required      pam_faillock.so authfail
      insertbefore: ^auth.*required.*pam_deny\.so.*
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_is_enabled.found == 0

  - name: Set Lockout Time for Failed Password Attempts - Enable pam_faillock.so account
      section editing PAM files
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      line: account     required      pam_faillock.so
      insertbefore: ^account.*required.*pam_unix\.so.*
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_is_enabled.found == 0
  when:
  - '"pam" in ansible_facts.packages'
  - not result_authselect_present.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_accounts_passwords_pam_faillock_unlock_time # promote to variable
  set_fact:
    var_accounts_passwords_pam_faillock_unlock_time: !!str 900
  tags:
    - always

- name: Set Lockout Time for Failed Password Attempts - Check the presence of /etc/security/faillock.conf
    file
  ansible.builtin.stat:
    path: /etc/security/faillock.conf
  register: result_faillock_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Ensure the pam_faillock.so
    unlock_time parameter in /etc/security/faillock.conf
  ansible.builtin.lineinfile:
    path: /etc/security/faillock.conf
    regexp: ^\s*unlock_time\s*=
    line: unlock_time = {{ var_accounts_passwords_pam_faillock_unlock_time }}
    state: present
  when:
  - '"pam" in ansible_facts.packages'
  - result_faillock_conf_check.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Ensure the pam_faillock.so
    unlock_time parameter not in PAM files
  block:

  - name: Set Lockout Time for Failed Password Attempts - Check if /etc/pam.d/system-auth
      file is present
    ansible.builtin.stat:
      path: /etc/pam.d/system-auth
    register: result_pam_file_present

  - name: Set Lockout Time for Failed Password Attempts - Check the proper remediation
      for the system
    block:

    - name: Set Lockout Time for Failed Password Attempts - Define the PAM file to
        be edited as a local fact
      ansible.builtin.set_fact:
        pam_file_path: /etc/pam.d/system-auth

    - name: Set Lockout Time for Failed Password Attempts - Check if system relies
        on authselect tool
      ansible.builtin.stat:
        path: /usr/bin/authselect
      register: result_authselect_present

    - name: Set Lockout Time for Failed Password Attempts - Ensure authselect custom
        profile is used if authselect is present
      block:

      - name: Set Lockout Time for Failed Password Attempts - Check integrity of authselect
          current profile
        ansible.builtin.command:
          cmd: authselect check
        register: result_authselect_check_cmd
        changed_when: false
        failed_when: false

      - name: Set Lockout Time for Failed Password Attempts - 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: Set Lockout Time for Failed Password Attempts - Get authselect current
          profile
        ansible.builtin.shell:
          cmd: authselect current -r | awk '{ print $1 }'
        register: result_authselect_profile
        changed_when: false
        when:
        - result_authselect_check_cmd is success

      - name: Set Lockout Time for Failed Password Attempts - Define the current authselect
          profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Define the new authselect
          custom profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: custom/hardening
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is not match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Get authselect current
          features to also enable them in the custom profile
        ansible.builtin.shell:
          cmd: authselect current | tail -n+3 | awk '{ print $2 }'
        register: result_authselect_features
        changed_when: false
        when:
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Check if any custom
          profile with the same name was already created
        ansible.builtin.stat:
          path: /etc/authselect/{{ authselect_custom_profile }}
        register: result_authselect_custom_profile_present
        changed_when: false
        when:
        - authselect_current_profile is not match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Create an authselect
          custom profile based on the current profile
        ansible.builtin.command:
          cmd: authselect create-profile hardening -b {{ authselect_current_profile
            }}
        when:
        - result_authselect_check_cmd is success
        - authselect_current_profile is not match("custom/")
        - not result_authselect_custom_profile_present.stat.exists

      - name: Set Lockout Time for Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Set Lockout Time for Failed Password Attempts - Ensure the authselect
          custom profile is selected
        ansible.builtin.command:
          cmd: authselect select {{ authselect_custom_profile }}
        register: result_pam_authselect_select_profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Set Lockout Time for Failed Password Attempts - Restore the authselect
          features in the custom profile
        ansible.builtin.command:
          cmd: authselect enable-feature {{ item }}
        loop: '{{ result_authselect_features.stdout_lines }}'
        register: result_pam_authselect_restore_features
        when:
        - result_authselect_profile is not skipped
        - result_authselect_features is not skipped
        - result_pam_authselect_select_profile is not skipped

      - name: Set Lockout Time for Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - result_pam_authselect_restore_features is not skipped

      - name: Set Lockout Time for Failed Password Attempts - Change the PAM file
          to be edited according to the custom authselect profile
        ansible.builtin.set_fact:
          pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
            | basename }}
      when:
      - result_authselect_present.stat.exists

    - name: Set Lockout Time for Failed Password Attempts - Define a fact for control
        already filtered in case filters are used
      ansible.builtin.set_fact:
        pam_module_control: ''

    - name: Set Lockout Time for Failed Password Attempts - Ensure the "unlock_time"
        option from "pam_faillock.so" is not present in {{ pam_file_path }}
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: (.*auth.*pam_faillock.so.*)\bunlock_time\b=?[0-9a-zA-Z]*(.*)
        replace: \1\2
      register: result_pam_option_removal

    - name: Set Lockout Time for Failed Password Attempts - Ensure authselect changes
        are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when:
      - result_authselect_present.stat.exists
      - result_pam_option_removal is changed
    when:
    - result_pam_file_present.stat.exists

  - name: Set Lockout Time for Failed Password Attempts - Check if /etc/pam.d/password-auth
      file is present
    ansible.builtin.stat:
      path: /etc/pam.d/password-auth
    register: result_pam_file_present

  - name: Set Lockout Time for Failed Password Attempts - Check the proper remediation
      for the system
    block:

    - name: Set Lockout Time for Failed Password Attempts - Define the PAM file to
        be edited as a local fact
      ansible.builtin.set_fact:
        pam_file_path: /etc/pam.d/password-auth

    - name: Set Lockout Time for Failed Password Attempts - Check if system relies
        on authselect tool
      ansible.builtin.stat:
        path: /usr/bin/authselect
      register: result_authselect_present

    - name: Set Lockout Time for Failed Password Attempts - Ensure authselect custom
        profile is used if authselect is present
      block:

      - name: Set Lockout Time for Failed Password Attempts - Check integrity of authselect
          current profile
        ansible.builtin.command:
          cmd: authselect check
        register: result_authselect_check_cmd
        changed_when: false
        failed_when: false

      - name: Set Lockout Time for Failed Password Attempts - 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: Set Lockout Time for Failed Password Attempts - Get authselect current
          profile
        ansible.builtin.shell:
          cmd: authselect current -r | awk '{ print $1 }'
        register: result_authselect_profile
        changed_when: false
        when:
        - result_authselect_check_cmd is success

      - name: Set Lockout Time for Failed Password Attempts - Define the current authselect
          profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Define the new authselect
          custom profile as a local fact
        ansible.builtin.set_fact:
          authselect_current_profile: '{{ result_authselect_profile.stdout }}'
          authselect_custom_profile: custom/hardening
        when:
        - result_authselect_profile is not skipped
        - result_authselect_profile.stdout is not match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Get authselect current
          features to also enable them in the custom profile
        ansible.builtin.shell:
          cmd: authselect current | tail -n+3 | awk '{ print $2 }'
        register: result_authselect_features
        changed_when: false
        when:
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Check if any custom
          profile with the same name was already created
        ansible.builtin.stat:
          path: /etc/authselect/{{ authselect_custom_profile }}
        register: result_authselect_custom_profile_present
        changed_when: false
        when:
        - authselect_current_profile is not match("custom/")

      - name: Set Lockout Time for Failed Password Attempts - Create an authselect
          custom profile based on the current profile
        ansible.builtin.command:
          cmd: authselect create-profile hardening -b {{ authselect_current_profile
            }}
        when:
        - result_authselect_check_cmd is success
        - authselect_current_profile is not match("custom/")
        - not result_authselect_custom_profile_present.stat.exists

      - name: Set Lockout Time for Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Set Lockout Time for Failed Password Attempts - Ensure the authselect
          custom profile is selected
        ansible.builtin.command:
          cmd: authselect select {{ authselect_custom_profile }}
        register: result_pam_authselect_select_profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - authselect_current_profile is not match("custom/")
        - authselect_custom_profile is not match(authselect_current_profile)

      - name: Set Lockout Time for Failed Password Attempts - Restore the authselect
          features in the custom profile
        ansible.builtin.command:
          cmd: authselect enable-feature {{ item }}
        loop: '{{ result_authselect_features.stdout_lines }}'
        register: result_pam_authselect_restore_features
        when:
        - result_authselect_profile is not skipped
        - result_authselect_features is not skipped
        - result_pam_authselect_select_profile is not skipped

      - name: Set Lockout Time for Failed Password Attempts - Ensure authselect changes
          are applied
        ansible.builtin.command:
          cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
        when:
        - result_authselect_check_cmd is success
        - result_authselect_profile is not skipped
        - result_pam_authselect_restore_features is not skipped

      - name: Set Lockout Time for Failed Password Attempts - Change the PAM file
          to be edited according to the custom authselect profile
        ansible.builtin.set_fact:
          pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
            | basename }}
      when:
      - result_authselect_present.stat.exists

    - name: Set Lockout Time for Failed Password Attempts - Define a fact for control
        already filtered in case filters are used
      ansible.builtin.set_fact:
        pam_module_control: ''

    - name: Set Lockout Time for Failed Password Attempts - Ensure the "unlock_time"
        option from "pam_faillock.so" is not present in {{ pam_file_path }}
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: (.*auth.*pam_faillock.so.*)\bunlock_time\b=?[0-9a-zA-Z]*(.*)
        replace: \1\2
      register: result_pam_option_removal

    - name: Set Lockout Time for Failed Password Attempts - Ensure authselect changes
        are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when:
      - result_authselect_present.stat.exists
      - result_pam_option_removal is changed
    when:
    - result_pam_file_present.stat.exists
  when:
  - '"pam" in ansible_facts.packages'
  - result_faillock_conf_check.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Lockout Time for Failed Password Attempts - Ensure the pam_faillock.so
    unlock_time parameter in PAM files
  block:

  - name: Set Lockout Time for Failed Password Attempts - Check if pam_faillock.so
      unlock_time parameter is already enabled in pam files
    ansible.builtin.lineinfile:
      path: /etc/pam.d/system-auth
      regexp: .*auth.*pam_faillock\.so (preauth|authfail).*unlock_time
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_faillock_unlock_time_parameter_is_present

  - name: Set Lockout Time for Failed Password Attempts - Ensure the inclusion of
      pam_faillock.so preauth unlock_time parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)
      line: \1required\3 unlock_time={{ var_accounts_passwords_pam_faillock_unlock_time
        }}
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_unlock_time_parameter_is_present.found == 0

  - name: Set Lockout Time for Failed Password Attempts - Ensure the inclusion of
      pam_faillock.so authfail unlock_time parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)
      line: \1required\3 unlock_time={{ var_accounts_passwords_pam_faillock_unlock_time
        }}
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_unlock_time_parameter_is_present.found == 0

  - name: Set Lockout Time for Failed Password Attempts - Ensure the desired value
      for pam_faillock.so preauth unlock_time parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so preauth.*)(unlock_time)=[0-9]+(.*)
      line: \1required\3\4={{ var_accounts_passwords_pam_faillock_unlock_time }}\5
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_unlock_time_parameter_is_present.found > 0

  - name: Set Lockout Time for Failed Password Attempts - Ensure the desired value
      for pam_faillock.so authfail unlock_time parameter in auth section
    ansible.builtin.lineinfile:
      path: '{{ item }}'
      backrefs: true
      regexp: (^\s*auth\s+)([\w\[].*\b)(\s+pam_faillock.so authfail.*)(unlock_time)=[0-9]+(.*)
      line: \1required\3\4={{ var_accounts_passwords_pam_faillock_unlock_time }}\5
      state: present
    loop:
    - /etc/pam.d/system-auth
    - /etc/pam.d/password-auth
    when:
    - result_pam_faillock_unlock_time_parameter_is_present.found > 0
  when:
  - '"pam" in ansible_facts.packages'
  - not result_faillock_conf_check.stat.exists
  tags:
  - CJIS-5.5.3
  - NIST-800-171-3.1.8
  - NIST-800-53-AC-7(b)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.1.7
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.4
  - accounts_passwords_pam_faillock_unlock_time
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
Group   Set Password Quality Requirements   Group contains 1 group and 3 rules
[ref]   The default pam_pwquality PAM module provides strength checking for passwords. It performs a number of checks, such as making sure passwords are not similar to dictionary words, are of at least a certain length, are not the previous password reversed, and are not simply a change of case from the previous password. It can also require passwords to be in certain character classes. The pam_pwquality module is the preferred way of configuring password requirements.

The man pages pam_pwquality(8) provide information on the capabilities and configuration of each.
Group   Set Password Quality Requirements with pam_pwquality   Group contains 3 rules
[ref]   The pam_pwquality PAM module can be configured to meet requirements for a variety of policies.

For example, to configure pam_pwquality to require at least one uppercase character, lowercase character, digit, and other (special) character, make sure that pam_pwquality exists in /etc/pam.d/system-auth:
password    requisite     pam_pwquality.so try_first_pass local_users_only retry=3 authtok_type=
If no such line exists, add one as the first line of the password section in /etc/pam.d/system-auth. Next, modify the settings in /etc/security/pwquality.conf to match the following:
difok = 4
minlen = 14
dcredit = -1
ucredit = -1
lcredit = -1
ocredit = -1
maxrepeat = 3
The arguments can be modified to ensure compliance with your organization's security policy. Discussion of each parameter follows.

Rule   Ensure PAM Enforces Password Requirements - Minimum Different Categories   [ref]

The pam_pwquality module's minclass parameter controls requirements for usage of different character classes, or types, of character that must exist in a password before it is considered valid. For example, setting this value to three (3) requires that any password must have characters from at least three different categories in order to be approved. The default value is zero (0), meaning there are no required classes. There are four categories available:
* Upper-case characters
* Lower-case characters
* Digits
* Special characters (for example, punctuation)
Modify the minclass setting in /etc/security/pwquality.conf entry to require 4 differing categories of characters when changing passwords.
Rationale:
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Requiring a minimum number of character categories makes password guessing attacks more difficult by ensuring a larger search space.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_minclass
References:
cis-csc1, 12, 15, 16, 5
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
disaCCI-004066
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
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
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
nistIA-5(c), IA-5(1)(a), CM-6(a), IA-5(4)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
os-srgSRG-OS-000072-GPOS-00040
anssiR68
cis4.5.1

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_minclass='4'








# 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' <<< "^minclass")

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

# 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 "^minclass\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^minclass\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(tail -c 1 -- "/etc/security/pwquality.conf" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/security/pwquality.conf"
    fi
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_minclass
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_minclass # promote to variable
  set_fact:
    var_password_pam_minclass: !!str 4
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Different Categories -
    Ensure PAM variable minclass is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*minclass
    line: minclass = {{ var_password_pam_minclass }}
  when: '"pam" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_minclass
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure PAM Enforces Password Requirements - Minimum Length   [ref]

The pam_pwquality module's minlen parameter controls requirements for minimum characters required in a password. Add minlen=14 after pam_pwquality to set minimum password length requirements.
Rationale:
The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.
Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Use of more characters in a password helps to exponentially increase the time and/or resources required to compromise the password.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_minlen
References:
cis-csc1, 12, 15, 16, 5
cjis5.6.2.1.1
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
disaCCI-004066
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
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
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
nistIA-5(c), IA-5(1)(a), CM-6(a), IA-5(4)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
osppFMT_SMF_EXT.1
pcidssReq-8.2.3
os-srgSRG-OS-000078-GPOS-00046
anssiR31, R68
cis4.5.1
pcidss48.3.6, 8.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_minlen='14'








# 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' <<< "^minlen")

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

# 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 "^minlen\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^minlen\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(tail -c 1 -- "/etc/security/pwquality.conf" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/security/pwquality.conf"
    fi
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.6.2.1.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_minlen
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_minlen # promote to variable
  set_fact:
    var_password_pam_minlen: !!str 14
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Length - Ensure PAM variable
    minlen is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*minlen
    line: minlen = {{ var_password_pam_minlen }}
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_minlen
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure PAM Enforces Password Requirements - Authentication Retry Prompts Permitted Per-Session   [ref]

To configure the number of retry prompts that are permitted per-session: Edit the pam_pwquality.so statement in /etc/pam.d/system-auth to show retry=3 , or a lower value if site policy is more restrictive. The DoD requirement is a maximum of 3 prompts per session.
Rationale:
Setting the password retry prompts that are permitted on a per-session basis to a low value requires some software, such as SSH, to re-connect. This can slow down and draw additional attention to some types of password-guessing attacks. Note that this is different from account lockout, which is provided by the pam_faillock module.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_retry
References:
cis-csc1, 11, 12, 15, 16, 3, 5, 9
cjis5.5.3
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
disaCCI-004066
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, 4.3.4.3.2, 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 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.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
nistCM-6(a), AC-7(a), IA-5(4)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7, PR.IP-1
os-srgSRG-OS-000069-GPOS-00037, SRG-OS-000480-GPOS-00227
anssiR68
cis4.5.1

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

var_password_pam_retry='3'



	
		if [ -e "/etc/pam.d/system-auth" ] ; then
    PAM_FILE_PATH="/etc/pam.d/system-auth"
    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

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "/etc/pam.d/system-auth")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
    fi
    

        if ! grep -qP "^\s*password\s+requisite\s+pam_pwquality.so\s*.*" "$PAM_FILE_PATH"; then
            # Line matching group + control + module was not found. Check group + module.
            if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwquality.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
                # The control is updated only if one single line matches.
                sed -i -E --follow-symlinks "s/^(\s*password\s+).*(\bpam_pwquality.so.*)/\1requisite \2/" "$PAM_FILE_PATH"
            else
                LAST_MATCH_LINE=$(grep -nP "^\s*account" "$PAM_FILE_PATH" | tail -n 1 | cut -d: -f 1)
                if [ ! -z $LAST_MATCH_LINE ]; then
                    sed -i --follow-symlinks $LAST_MATCH_LINE" a password     requisite    pam_pwquality.so" "$PAM_FILE_PATH"
                else
                    echo "password    requisite    pam_pwquality.so" >> "$PAM_FILE_PATH"
                fi
            fi
        fi
        # Check the option
        if ! grep -qP "^\s*password\s+requisite\s+pam_pwquality.so\s*.*\sretry\b" "$PAM_FILE_PATH"; then
            sed -i -E --follow-symlinks "/\s*password\s+requisite\s+pam_pwquality.so.*/ s/$/ retry=$var_password_pam_retry/" "$PAM_FILE_PATH"
        else
            sed -i -E --follow-symlinks "s/(\s*password\s+requisite\s+pam_pwquality.so\s+.*)(retry=)[[:alnum:]]+\s*(.*)/\1\2$var_password_pam_retry \3/" "$PAM_FILE_PATH"
        fi
    if [ -f /usr/bin/authselect ]; then
        
        authselect apply-changes -b
    fi
else
    echo "/etc/pam.d/system-auth was not found" >&2
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Set Password Hashing Algorithm   Group contains 3 rules
[ref]   The system's default algorithm for storing password hashes in /etc/shadow is SHA-512. This can be configured in several locations.

Rule   Set Password Hashing Algorithm in /etc/login.defs   [ref]

In /etc/login.defs, add or update the following line to ensure the system will use SHA512 as the hashing algorithm:
ENCRYPT_METHOD SHA512
         
Rationale:
Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kept in plain text.

Using a stronger hashing algorithm makes password cracking attacks more difficult.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_logindefs
References:
cis-csc1, 12, 15, 16, 5
cjis5.6.2.2
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.13.11
disaCCI-004062
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
ism0418, 1055, 1402
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
nistIA-5(c), IA-5(1)(c), CM-6(a)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
pcidssReq-8.2.1
os-srgSRG-OS-000073-GPOS-00041
cis4.5.4
pcidss48.3.2, 8.3

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

var_password_hashing_algorithm='SHA512'


# Allow multiple algorithms, but choose the first one for remediation
#
var_password_hashing_algorithm="$(echo $var_password_hashing_algorithm | cut -d \| -f 1)"

# 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' <<< "^ENCRYPT_METHOD")

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

# 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 "^ENCRYPT_METHOD\\>" "/etc/login.defs"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^ENCRYPT_METHOD\\>.*/$escaped_formatted_output/gi" "/etc/login.defs"
else
    if [[ -s "/etc/login.defs" ]] && [[ -n "$(tail -c 1 -- "/etc/login.defs" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/login.defs"
    fi
    printf '%s\n' "$formatted_output" >> "/etc/login.defs"
fi

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

Rule   Set PAM''s Password Hashing Algorithm - password-auth   [ref]

The PAM system service can be configured to only store encrypted representations of passwords. In /etc/pam.d/password-auth, the password section of the file controls which PAM modules to execute during a password change. Set the pam_unix.so module in the password section to include the option sha512 and no other hashing algorithms as shown below:
password    sufficient    pam_unix.so sha512
          other arguments...
         

This will help ensure that new passwords for local users will be stored using the sha512 algorithm.
Warning:  The hashing algorithms to be used with pam_unix.so are defined with independent module options. There are at least 7 possible algorithms and likely more algorithms will be introduced along the time. Due the the number of options and its possible combinations, the use of multiple hashing algorithm options may bring unexpected behaviors to the system. For this reason the check will pass only when one hashing algorithm option is defined and is aligned to the "var_password_hashing_algorithm_pam" variable. The remediation will ensure the correct option and remove any other extra hashing algorithm option.
Rationale:
Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kept in plain text.

This setting ensures user and group account administration utilities are configured to store only encrypted representations of passwords. Additionally, the crypt_style configuration option in /etc/libuser.conf ensures the use of a strong hashing algorithm that makes password cracking attacks more difficult.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_passwordauth
References:
cis-csc1, 12, 15, 16, 5
cjis5.6.2.2
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.13.11
disaCCI-004062
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
ism0418, 1055, 1402
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
nistIA-5(c), IA-5(1)(c), CM-6(a)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
pcidssReq-8.2.1
os-srgSRG-OS-000073-GPOS-00041, SRG-OS-000120-GPOS-00061
cis4.5.4

Rule   Set PAM''s Password Hashing Algorithm   [ref]

The PAM system service can be configured to only store encrypted representations of passwords. In "/etc/pam.d/system-auth", the password section of the file controls which PAM modules to execute during a password change. Set the pam_unix.so module in the password section to include the option sha512 and no other hashing algorithms as shown below:
password    sufficient    pam_unix.so sha512
          other arguments...
         

This will help ensure that new passwords for local users will be stored using the sha512 algorithm.
Warning:  The hashing algorithms to be used with pam_unix.so are defined with independent module options. There are at least 7 possible algorithms and likely more algorithms will be introduced along the time. Due the the number of options and its possible combinations, the use of multiple hashing algorithm options may bring unexpected behaviors to the system. For this reason the check will pass only when one hashing algorithm option is defined and is aligned to the "var_password_hashing_algorithm_pam" variable. The remediation will ensure the correct option and remove any other extra hashing algorithm option.
Rationale:
Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kept in plain text.

This setting ensures user and group account administration utilities are configured to store only encrypted representations of passwords. Additionally, the crypt_style configuration option in /etc/libuser.conf ensures the use of a strong hashing algorithm that makes password cracking attacks more difficult.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_systemauth
References:
cis-csc1, 12, 15, 16, 5
cjis5.6.2.2
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.13.11
disaCCI-000196, CCI-000803, CCI-004062
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
ism0418, 1055, 1402
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
nistIA-5(c), IA-5(1)(c), CM-6(a)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
pcidssReq-8.2.1
os-srgSRG-OS-000073-GPOS-00041, SRG-OS-000120-GPOS-00061
anssiR68
cis4.5.4
pcidss48.3.2, 8.3

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

var_password_hashing_algorithm_pam='sha512'


PAM_FILE_PATH="/etc/pam.d/system-auth"
CONTROL="sufficient"

if [ -e "$PAM_FILE_PATH" ] ; then
    PAM_FILE_PATH="$PAM_FILE_PATH"
    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

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "$PAM_FILE_PATH")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
    fi
    

        if ! grep -qP "^\s*password\s+\$CONTROL\s+pam_unix.so\s*.*" "$PAM_FILE_PATH"; then
            # Line matching group + control + module was not found. Check group + module.
            if [ "$(grep -cP '^\s*password\s+.*\s+pam_unix.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
                # The control is updated only if one single line matches.
                sed -i -E --follow-symlinks "s/^(\s*password\s+).*(\bpam_unix.so.*)/\1$CONTROL \2/" "$PAM_FILE_PATH"
            else
                echo "password    $CONTROL    pam_unix.so" >> "$PAM_FILE_PATH"
            fi
        fi
        # Check the option
        if ! grep -qP "^\s*password\s+\$CONTROL\s+pam_unix.so\s*.*\s$var_password_hashing_algorithm_pam\b" "$PAM_FILE_PATH"; then
            sed -i -E --follow-symlinks "/\s*password\s+\$CONTROL\s+pam_unix.so.*/ s/$/ $var_password_hashing_algorithm_pam/" "$PAM_FILE_PATH"
        fi
    if [ -f /usr/bin/authselect ]; then
        
        authselect apply-changes -b
    fi
else
    echo "$PAM_FILE_PATH was not found" >&2
fi

# Ensure only the correct hashing algorithm option is used.
declare -a HASHING_ALGORITHMS_OPTIONS=("sha512" "yescrypt" "gost_yescrypt" "blowfish" "sha256" "md5" "bigcrypt")

for hash_option in "${HASHING_ALGORITHMS_OPTIONS[@]}"; do
  if [ "$hash_option" != "$var_password_hashing_algorithm_pam" ]; then
    if grep -qP "^\s*password\s+.*\s+pam_unix.so\s+.*\b$hash_option\b" "$PAM_FILE_PATH"; then
      if [ -e "$PAM_FILE_PATH" ] ; then
    PAM_FILE_PATH="$PAM_FILE_PATH"
    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

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "$PAM_FILE_PATH")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
    fi
    
if grep -qP "^\s*password\s+.*\s+pam_unix.so\s.*\b$hash_option\b" "$PAM_FILE_PATH"; then
    sed -i -E --follow-symlinks "s/(.*password.*.*.*pam_unix.so.*)\s$hash_option=?[[:alnum:]]*(.*)/\1\2/g" "$PAM_FILE_PATH"
fi
    if [ -f /usr/bin/authselect ]; then
        
        authselect apply-changes -b
    fi
else
    echo "$PAM_FILE_PATH was not found" >&2
fi
    fi
  fi
done

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

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.6.2.2
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth
- name: XCCDF Value var_password_hashing_algorithm_pam # promote to variable
  set_fact:
    var_password_hashing_algorithm_pam: !!str sha512
  tags:
    - always

- name: Set PAM's Password Hashing Algorithm - Check if /etc/pam.d/system-auth file
    is present
  ansible.builtin.stat:
    path: /etc/pam.d/system-auth
  register: result_pam_file_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.2
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth

- name: Set PAM's Password Hashing Algorithm - Check the proper remediation for the
    system
  block:

  - name: Set PAM's Password Hashing Algorithm - Define the PAM file to be edited
      as a local fact
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/system-auth

  - name: Set PAM's Password Hashing Algorithm - Check if system relies on authselect
      tool
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: Set PAM's Password Hashing Algorithm - Ensure authselect custom profile
      is used if authselect is present
    block:

    - name: Set PAM's Password Hashing Algorithm - Check integrity of authselect current
        profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      failed_when: false

    - name: Set PAM's Password Hashing Algorithm - 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: Set PAM's Password Hashing Algorithm - Get authselect current profile
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: Set PAM's Password Hashing Algorithm - Define the current authselect profile
        as a local fact
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Define the new authselect custom
        profile as a local fact
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Get authselect current features
        to also enable them in the custom profile
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Check if any custom profile with
        the same name was already created
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Create an authselect custom profile
        based on the current profile
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: Set PAM's Password Hashing Algorithm - Ensure the authselect custom profile
        is selected
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: Set PAM's Password Hashing Algorithm - Restore the authselect features
        in the custom profile
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: Set PAM's Password Hashing Algorithm - Change the PAM file to be edited
        according to the custom authselect profile
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: Set PAM's Password Hashing Algorithm - Define a fact for control already
      filtered in case filters are used
    ansible.builtin.set_fact:
      pam_module_control: sufficient

  - name: Set PAM's Password Hashing Algorithm - Check if expected PAM module line
      is present in {{ pam_file_path }}
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+{{ pam_module_control | regex_escape() }}\s+pam_unix.so\s*.*
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_line_present

  - name: Set PAM's Password Hashing Algorithm - Include or update the PAM module
      line in {{ pam_file_path }}
    block:

    - name: Set PAM's Password Hashing Algorithm - Check if required PAM module line
        is present in {{ pam_file_path }} with different control
      ansible.builtin.lineinfile:
        path: '{{ pam_file_path }}'
        regexp: ^\s*password\s+.*\s+pam_unix.so\s*
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_line_other_control_present

    - name: Set PAM's Password Hashing Algorithm - Ensure the correct control for
        the required PAM module line in {{ pam_file_path }}
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: ^(\s*password\s+).*(\bpam_unix.so.*)
        replace: \1{{ pam_module_control }} \2
      register: result_pam_module_edit
      when:
      - result_pam_line_other_control_present.found == 1

    - name: Set PAM's Password Hashing Algorithm - Ensure the required PAM module
        line is included in {{ pam_file_path }}
      ansible.builtin.lineinfile:
        dest: '{{ pam_file_path }}'
        line: password    {{ pam_module_control }}    pam_unix.so
      register: result_pam_module_add
      when:
      - result_pam_line_other_control_present.found == 0 or result_pam_line_other_control_present.found
        > 1

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when:
      - result_authselect_present is defined
      - result_authselect_present.stat.exists
      - |-
        (result_pam_module_add is defined and result_pam_module_add.changed)
         or (result_pam_module_edit is defined and result_pam_module_edit.changed)
    when:
    - result_pam_line_present.found is defined
    - result_pam_line_present.found == 0

  - name: Set PAM's Password Hashing Algorithm - Define a fact for control already
      filtered in case filters are used
    ansible.builtin.set_fact:
      pam_module_control: sufficient

  - name: Set PAM's Password Hashing Algorithm - Check if the required PAM module
      option is present in {{ pam_file_path }}
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+{{ pam_module_control | regex_escape() }}\s+pam_unix.so\s*.*\s{{
        var_password_hashing_algorithm_pam }}\b
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_module_set_password_hashing_algorithm_systemauth_option_present

  - name: Set PAM's Password Hashing Algorithm - Ensure the "{{ var_password_hashing_algorithm_pam
      }}" PAM option for "pam_unix.so" is included in {{ pam_file_path }}
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      backrefs: true
      regexp: ^(\s*password\s+{{ pam_module_control | regex_escape() }}\s+pam_unix.so.*)
      line: \1 {{ var_password_hashing_algorithm_pam }}
      state: present
    register: result_pam_set_password_hashing_algorithm_systemauth_add
    when:
    - result_pam_module_set_password_hashing_algorithm_systemauth_option_present.found
      == 0

  - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_present.stat.exists
    - |-
      (result_pam_set_password_hashing_algorithm_systemauth_add is defined and result_pam_set_password_hashing_algorithm_systemauth_add.changed)
       or (result_pam_set_password_hashing_algorithm_systemauth_edit is defined and result_pam_set_password_hashing_algorithm_systemauth_edit.changed)
  when:
  - '"pam" in ansible_facts.packages'
  - result_pam_file_present.stat.exists
  tags:
  - CJIS-5.6.2.2
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth

- name: Set PAM's Password Hashing Algorithm - Check if /etc/pam.d/system-auth File
    is Present
  ansible.builtin.stat:
    path: /etc/pam.d/system-auth
  register: result_pam_file_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.2
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth

- name: Set PAM's Password Hashing Algorithm - Check The Proper Remediation For The
    System
  block:

  - name: Set PAM's Password Hashing Algorithm - Define the PAM file to be edited
      as a local fact
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/system-auth

  - name: Set PAM's Password Hashing Algorithm - Check if system relies on authselect
      tool
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: Set PAM's Password Hashing Algorithm - Ensure authselect custom profile
      is used if authselect is present
    block:

    - name: Set PAM's Password Hashing Algorithm - Check integrity of authselect current
        profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      failed_when: false

    - name: Set PAM's Password Hashing Algorithm - 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: Set PAM's Password Hashing Algorithm - Get authselect current profile
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: Set PAM's Password Hashing Algorithm - Define the current authselect profile
        as a local fact
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Define the new authselect custom
        profile as a local fact
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Get authselect current features
        to also enable them in the custom profile
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Check if any custom profile with
        the same name was already created
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Create an authselect custom profile
        based on the current profile
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: Set PAM's Password Hashing Algorithm - Ensure the authselect custom profile
        is selected
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: Set PAM's Password Hashing Algorithm - Restore the authselect features
        in the custom profile
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: Set PAM's Password Hashing Algorithm - Change the PAM file to be edited
        according to the custom authselect profile
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: Set PAM's Password Hashing Algorithm - Ensure That Only the Correct Hashing
      Algorithm Option For pam_unix.so Is Used in /etc/pam.d/system-auth
    ansible.builtin.replace:
      dest: '{{ pam_file_path }}'
      regexp: (^\s*password.*pam_unix\.so.*)\b{{ item }}\b\s*(.*)
      replace: \1\2
    when: item != var_password_hashing_algorithm_pam
    loop:
    - sha512
    - yescrypt
    - gost_yescrypt
    - blowfish
    - sha256
    - md5
    - bigcrypt
    register: result_pam_hashing_options_removal

  - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_present.stat.exists
    - result_pam_hashing_options_removal is changed
  when:
  - '"pam" in ansible_facts.packages'
  - result_pam_file_present.stat.exists
  tags:
  - CJIS-5.6.2.2
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth
Group   Protect Accounts by Restricting Password-Based Login   Group contains 4 groups and 24 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   Set Account Expiration Parameters   Group contains 2 rules
Group   Set Password Expiration Parameters   Group contains 7 rules
[ref]   The file /etc/login.defs controls several password-related settings. Programs such as passwd, su, and login consult /etc/login.defs to determine behavior with regard to password aging, expiration warnings, and length. See the man page login.defs(5) for more information.

Users should be forced to change their passwords, in order to decrease the utility of compromised passwords. However, the need to change passwords often should be balanced against the risk that users will reuse or write down passwords if forced to change them too often. Forcing password changes every 90-360 days, depending on the environment, is recommended. Set the appropriate value as PASS_MAX_DAYS and apply it to existing accounts with the -M flag.

The PASS_MIN_DAYS (-m) setting prevents password changes for 7 days after the first change, to discourage password cycling. If you use this setting, train users to contact an administrator for an emergency password change in case a new password becomes compromised. The PASS_WARN_AGE (-W) setting gives users 7 days of warnings at login time that their passwords are about to expire.

For example, for each existing human user USER, expiration parameters could be adjusted to a 180 day maximum password age, 7 day minimum password age, and 7 day warning period with the following command:
$ sudo chage -M 180 -m 7 -W 7 USER

Rule   Set Existing Passwords Maximum Age   [ref]

Configure non-compliant accounts to enforce a 365-day maximum password lifetime restriction by running the following command:
$ sudo chage -M 365
          USER
         
Rationale:
Any password, no matter how complex, can eventually be cracked. Therefore, passwords need to be changed periodically. If the operating system does not limit the lifetime of passwords and force users to change their passwords, there is the risk that the operating system passwords could be compromised.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_set_max_life_existing
References:
disaCCI-004066
nistIA-5(f), IA-5(1)(d), CM-6(a)
os-srgSRG-OS-000076-GPOS-00044
cis4.6.1.1
pcidss48.3.9, 8.3

Rule   Set Existing Passwords Minimum Age   [ref]

Configure non-compliant accounts to enforce a 24 hours/1 day minimum password lifetime by running the following command:
$ sudo chage -m 1 USER
         
Rationale:
Enforcing a minimum password lifetime helps to prevent repeated password changes to defeat the password reuse or history enforcement requirement. If users are allowed to immediately and continually change their password, the password could be repeatedly changed in a short period of time to defeat the organization's policy regarding password reuse.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_set_min_life_existing
References:
disaCCI-004066
nistIA-5(f), IA-5(1)(d), CM-6(a)
os-srgSRG-OS-000075-GPOS-00043
cis4.6.1.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

var_accounts_minimum_age_login_defs='1'


while IFS= read -r i; do
    
    chage -m $var_accounts_minimum_age_login_defs $i

done <   <(awk -v var="$var_accounts_minimum_age_login_defs" -F: '(/^[^:]+:[^!*]/ && ($4 < var || $4 == "")) {print $1}' /etc/shadow)

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value var_accounts_minimum_age_login_defs # promote to variable
  set_fact:
    var_accounts_minimum_age_login_defs: !!str 1
  tags:
    - always

- name: Collect users with not correct minimum time period between password changes
  command: |
    awk -F':' '(/^[^:]+:[^!*]/ && ($4 < {{ var_accounts_minimum_age_login_defs }} || $4 == "")) {print $1}' /etc/shadow
  register: user_names
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(d)
  - NIST-800-53-IA-5(f)
  - accounts_password_set_min_life_existing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Change the minimum time period between password changes
  command: |
    chage -m {{ var_accounts_minimum_age_login_defs }} {{ item }}
  with_items: '{{ user_names.stdout_lines }}'
  when: user_names.stdout_lines | length > 0
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(d)
  - NIST-800-53-IA-5(f)
  - accounts_password_set_min_life_existing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Set Existing Passwords Warning Age   [ref]

To configure how many days prior to password expiration that a warning will be issued to users, run the command:
$ sudo chage --warndays 7
          USER
         
The DoD requirement is 7, and CIS recommendation is no less than 7 days. This profile requirement is 7.
Rationale:
Providing an advance warning that a password will be expiring gives users time to think of a secure password. Users caught unaware may choose a simple password or write it down where it may be discovered.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_set_warn_age_existing
References:
disaCCI-000198
nistIA-5(f), IA-5(1)(d), CM-6(a)
cis4.6.1.3
pcidss48.3.9, 8.3

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

var_accounts_password_warn_age_login_defs='7'


while IFS= read -r i; do
    chage --warndays $var_accounts_password_warn_age_login_defs $i
done <   <(awk -v var="$var_accounts_password_warn_age_login_defs" -F: '(($6 < var || $6 == "") && $2 ~ /^\$/) {print $1}' /etc/shadow)

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: XCCDF Value var_accounts_password_warn_age_login_defs # promote to variable
  set_fact:
    var_accounts_password_warn_age_login_defs: !!str 7
  tags:
    - always

- name: Set Existing Passwords Warning Age - Collect Users With Incorrect Number of
    Days of Warning Before Password Expires
  ansible.builtin.command:
    cmd: awk -F':' '(($6 < {{ var_accounts_password_warn_age_login_defs }} || $6 ==
      "") && $2 ~ /^\$/) {print $1}' /etc/shadow
  register: result_pass_warn_age_user_names
  changed_when: false
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(d)
  - NIST-800-53-IA-5(f)
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.9
  - accounts_password_set_warn_age_existing
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set Existing Passwords Warning Age - Ensure the Number of Days of Warning
    Before Password Expires
  ansible.builtin.command:
    cmd: chage --warndays {{ var_accounts_password_warn_age_login_defs }} {{ item
      }}
  with_items: '{{ result_pass_warn_age_user_names.stdout_lines }}'
  when: result_pass_warn_age_user_names is not skipped and result_pass_warn_age_user_names.stdout_lines
    | length > 0
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(d)
  - NIST-800-53-IA-5(f)
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.9
  - accounts_password_set_warn_age_existing
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Set existing passwords a period of inactivity before they been locked   [ref]

Configure user accounts that have been inactive for over a given period of time to be automatically disabled by running the following command:
$ sudo chage --inactive 30USER
         
Rationale:
Inactive accounts pose a threat to system security since the users are not logging in to notice failed login attempts or other anomalies.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_set_post_pw_existing
References:
cobit5DSS01.03, DSS03.05, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.5.6
disaCCI-000017, CCI-000795, CCI-003627, CCI-003628
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 6.2
iso27001-2013A.12.4.1, A.12.4.3, A.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-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
nistIA-4(e), AC-2(3), CM-6(a)
nist-csfDE.CM-1, DE.CM-3, PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7
pcidssReq-8.1.4
os-srgSRG-OS-000118-GPOS-00060
cis4.6.1.4
pcidss48.2.6, 8.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

var_account_disable_post_pw_expiration='30'


while IFS= read -r i; do
    chage --inactive $var_account_disable_post_pw_expiration $i
done <   <(awk -v var="$var_account_disable_post_pw_expiration" -F: '(($7 > var || $7 == "") && $2 ~ /^\$/) {print $1}' /etc/shadow)

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value var_account_disable_post_pw_expiration # promote to variable
  set_fact:
    var_account_disable_post_pw_expiration: !!str 30
  tags:
    - always

- name: Collect users with not correct INACTIVE parameter set
  ansible.builtin.command:
    cmd: awk -F':' '(($7 > {{ var_account_disable_post_pw_expiration }} || $7 == "")
      && $2 ~ /^\$/) {print $1}' /etc/shadow
  register: user_names
  changed_when: false
  tags:
  - NIST-800-171-3.5.6
  - NIST-800-53-AC-2(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-4(e)
  - PCI-DSS-Req-8.1.4
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.6
  - accounts_set_post_pw_existing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Change the period of inactivity
  ansible.builtin.command:
    cmd: chage --inactive {{ var_account_disable_post_pw_expiration }} {{ item }}
  with_items: '{{ user_names.stdout_lines }}'
  when: user_names is not skipped and user_names.stdout_lines | length > 0
  tags:
  - NIST-800-171-3.5.6
  - NIST-800-53-AC-2(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-4(e)
  - PCI-DSS-Req-8.1.4
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.6
  - accounts_set_post_pw_existing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
Group   Verify Proper Storage and Existence of Password Hashes   Group contains 5 rules
[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   Verify All Account Password Hashes are Shadowed   [ref]

If any password hashes are stored in /etc/passwd (in the second field, instead of an x or *), the cause of this misconfiguration should be investigated. The account should have its password reset and the hash should be properly stored, or the account should be deleted entirely.
Rationale:
The hashes for all user account passwords should be stored in the file /etc/shadow and never in /etc/passwd, which is readable by all users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_all_shadowed
References:
cis-csc1, 12, 15, 16, 5
cjis5.5.2
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
cui3.5.10
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
ism1410
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
nistIA-5(h), CM-6(a)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
pcidssReq-8.2.1
cis6.2.1
pcidss48.3.2, 8.3

Rule   Ensure all users last password change date is in the past   [ref]

All users should have a password change date in the past.
Warning:  Automatic remediation is not available, in order to avoid any system disruption.
Rationale:
If a user recorded password change date is in the future then they could bypass any set password expiration.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_last_change_is_in_past
References:
cis4.6.1.5
pcidss48.3.5, 8.3

Rule   All GIDs referenced in /etc/passwd must be defined in /etc/group   [ref]

Add a group to the system for each GID referenced without a corresponding group.
Rationale:
If a user is assigned the Group Identifier (GID) of a group not existing on the system, and a group with the Group Identifier (GID) is subsequently created, the user may have unintended rights to any files associated with the group.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_gid_passwd_group_same
References:
cis-csc1, 12, 15, 16, 5
cjis5.5.2
cobit5DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10
disaCCI-000764
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
pcidssReq-8.5.a
os-srgSRG-OS-000104-GPOS-00051
cis6.2.3
pcidss48.2.2, 8.2

Rule   Ensure There Are No Accounts With Blank or Null Passwords   [ref]

Check the "/etc/shadow" file for blank passwords with the following command:
$ sudo awk -F: '!$2 {print $1}' /etc/shadow
If the command returns any results, this is a finding. Configure all accounts on the system to have a password or lock the account with the following commands: Perform a password reset:
$ sudo passwd [username]
Lock an account:
$ sudo passwd -l [username]
Warning:  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_etc_shadow
References:
disaCCI-000366
nistCM-6(b), CM-6.1(iv)
os-srgSRG-OS-000480-GPOS-00227
cis4.6.6, 6.2.2
pcidss42.2.2, 2.2

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

readarray -t users_with_empty_pass < <(sudo awk -F: '!$2 {print $1}' /etc/shadow)

for user_with_empty_pass in "${users_with_empty_pass[@]}"
do
    passwd -l $user_with_empty_pass
done

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.2
  - high_severity
  - low_complexity
  - low_disruption
  - no_empty_passwords_etc_shadow
  - no_reboot_needed
  - restrict_strategy

- name: Collect users with no password
  command: |
    awk -F: '!$2 {print $1}' /etc/shadow
  register: users_nopasswd
  changed_when: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.2
  - high_severity
  - low_complexity
  - low_disruption
  - no_empty_passwords_etc_shadow
  - no_reboot_needed
  - restrict_strategy

- name: Lock users with no password
  command: |
    passwd -l {{ item }}
  with_items: '{{ users_nopasswd.stdout_lines }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - users_nopasswd is not skipped and users_nopasswd.stdout_lines | length > 0
  tags:
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.2
  - high_severity
  - low_complexity
  - low_disruption
  - no_empty_passwords_etc_shadow
  - no_reboot_needed
  - restrict_strategy

Rule   Verify No .forward Files Exist   [ref]

The .forward file specifies an email address to forward the user's mail to.
Rationale:
Use of the .forward file poses a security risk in that sensitive data may be inadvertently transferred outside the organization. The .forward file also poses a risk as it can be used to execute commands that may perform unintended actions.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_forward_files
References:
cis6.2.11
Group   Restrict Root Logins   Group contains 7 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   Verify Only Root Has UID 0   [ref]

If any account other than root has a UID of 0, this misconfiguration should be investigated and the accounts other than root should be removed or have their UID changed.
If the account is associated with system commands or applications the UID should be changed to one greater than "0" but less than "1000." Otherwise assign a UID greater than "1000" that has not already been assigned.
Rationale:
An account has root authority if it has a UID of 0. Multiple accounts with a UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account. Proper configuration of sudo is recommended to afford multiple system administrators access to root privileges in an accountable manner.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_accounts_no_uid_except_zero
References:
cis-csc1, 12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.02, DSS06.03, DSS06.10
cui3.1.1, 3.1.5
disaCCI-000366
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
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-6(5), IA-4(b)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.DS-5
pcidssReq-8.5
os-srgSRG-OS-000480-GPOS-00227
cis6.2.9
pcidss48.2.1, 8.2

awk -F: '$3 == 0 && $1 != "root" { print $1 }' /etc/passwd | xargs --no-run-if-empty --max-lines=1 passwd -l

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Get all /etc/passwd file entries
  getent:
    database: passwd
    split: ':'
  tags:
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-AC-6(5)
  - NIST-800-53-IA-2
  - NIST-800-53-IA-4(b)
  - PCI-DSS-Req-8.5
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.1
  - accounts_no_uid_except_zero
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy

- name: Lock the password of the user accounts other than root with uid 0
  command: passwd -l {{ item.key }}
  loop: '{{ getent_passwd | dict2items | rejectattr(''key'', ''search'', ''root'')
    | list }}'
  when: item.value.1  == '0'
  tags:
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-AC-6(5)
  - NIST-800-53-IA-2
  - NIST-800-53-IA-4(b)
  - PCI-DSS-Req-8.5
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.1
  - accounts_no_uid_except_zero
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy

Rule   Verify Root Has A Primary GID 0   [ref]

The root user should have a primary group of 0.
Rationale:
To help ensure that root-owned files are not inadvertently exposed to other users.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_accounts_root_gid_zero
References:
pcidssReq-8.1.1
cis4.6.4
pcidss48.2.1, 8.2

Rule   Ensure the Group Used by pam_wheel.so Module Exists on System and is Empty   [ref]

Ensure that the group sugroup referenced by var_pam_wheel_group_for_su variable and used as value for the pam_wheel.so group option exists and has no members. This empty group used by pam_wheel.so in /etc/pam.d/su ensures that no user can run commands with altered privileges through the su command.
Warning:  Note that this rule just ensures the group exists and has no members. This rule does not configure pam_wheel.so module. The pam_wheel.so module configuration is accomplished by use_pam_wheel_group_for_su rule.
Rationale:
The su program allows to run commands with a substitute user and group ID. It is commonly used to run commands as the root user. Limiting access to such command is considered a good security practice.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ensure_pam_wheel_group_empty
References:
cis4.3.6
pcidss42.2.6, 2.2

Rule   Ensure Authentication Required for Single User Mode   [ref]

Single user mode is used for recovery when the system detects an issue during boot or by manual selection from the bootloader.
Rationale:
Requiring authentication in single user mode prevents an unauthorized user from rebooting the system into single user to gain root privileges without credentials.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ensure_root_password_configured
References:
cis4.6.6
pcidss42.2.2, 2.2

Rule   Ensure that System Accounts Are Locked   [ref]

Some accounts are not associated with a human user of the system, and exist to perform some administrative functions. An attacker should not be able to log into these accounts.

System accounts are those user accounts with a user ID less than 1000. If any system account other than root, halt, sync, shutdown and nfsnobody has an unlocked password, disable it with the command:
$ sudo usermod -L account
         
Rationale:
Disabling authentication for default system accounts makes it more difficult for attackers to make use of them to compromise a system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_password_auth_for_systemaccounts
References:
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)
cis4.6.2
pcidss48.2.2, 8.2

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

readarray -t systemaccounts < <(awk -F: \
  '($3 < 1000 && $3 != root && $3 != halt && $3 != sync && $3 != shutdown \
  && $3 != nfsnobody) { print $1 }' /etc/passwd)

for systemaccount in "${systemaccounts[@]}"; do
    usermod -L "$systemaccount"
done

Complexity:low
Disruption:medium
Reboot:false
Strategy:restrict
- name: Ensure that System Accounts Are Locked - Get All Local Users From /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.2
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_password_auth_for_systemaccounts
  - no_reboot_needed
  - restrict_strategy

- name: Ensure that System Accounts Are Locked - Create local_users Variable From
    getent_passwd Facts
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd | dict2items }}'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.2
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_password_auth_for_systemaccounts
  - no_reboot_needed
  - restrict_strategy

- name: Ensure that System Accounts Are Locked - Lock System Accounts
  ansible.builtin.user:
    name: '{{ item.key }}'
    password_lock: true
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int < 1000
  - item.key not in ['root', 'halt', 'sync', 'shutdown', 'nfsnobody']
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.2
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_password_auth_for_systemaccounts
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure that System Accounts Do Not Run a Shell Upon Login   [ref]

Some accounts are not associated with a human user of the system, and exist to perform some administrative functions. Should an attacker be able to log into these accounts, they should not be granted access to a shell.

The login shell for each local account is stored in the last field of each line in /etc/passwd. System accounts are those user accounts with a user ID less than 1000. The user ID is stored in the third field. If any system account other than root has a login shell, disable it with the command:
$ sudo usermod -s /sbin/nologin account
         
Warning:  Do not perform the steps in this section on the root account. Doing so might cause the system to become inaccessible.
Rationale:
Ensuring shells are not given to system accounts upon login makes it more difficult for attackers to make use of system accounts.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_shelllogin_for_systemaccounts
References:
cis-csc1, 12, 13, 14, 15, 16, 18, 3, 5, 7, 8
cobit5DSS01.03, DSS03.05, DSS05.04, DSS05.05, DSS05.07, DSS06.03
disaCCI-000366
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, 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
ism1491
iso27001-2013A.12.4.1, A.12.4.3, 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
nistAC-6, CM-6(a), CM-6(b), CM-6.1(iv)
nist-csfDE.CM-1, DE.CM-3, PR.AC-1, PR.AC-4, PR.AC-6
os-srgSRG-OS-000480-GPOS-00227
cis4.6.2
pcidss48.2.2, 8.2

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

readarray -t systemaccounts < <(awk -F: '($3 < 1000 && $3 != root \
  && $7 != "\/sbin\/shutdown" && $7 != "\/sbin\/halt" && $7 != "\/bin\/sync") \
  { print $1 }' /etc/passwd)

for systemaccount in "${systemaccounts[@]}"; do
    usermod -s /sbin/nologin "$systemaccount"
done

Complexity:low
Disruption:medium
Reboot:false
Strategy:restrict
- name: Ensure that System Accounts Do Not Run a Shell Upon Login - Get All Local
    Users From /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.2
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - no_shelllogin_for_systemaccounts
  - restrict_strategy

- name: Ensure that System Accounts Do Not Run a Shell Upon Login - Create local_users
    Variable From getent_passwd Facts
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd | dict2items }}'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.2
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - no_shelllogin_for_systemaccounts
  - restrict_strategy

- name: Ensure that System Accounts Do Not Run a Shell Upon Login -  Disable Login
    Shell for System Accounts
  ansible.builtin.user:
    name: '{{ item.key }}'
    shell: /sbin/nologin
  loop: '{{ local_users }}'
  when:
  - item.key not in ['root']
  - item.value[1]|int < 1000
  - item.value[5] not in ['/sbin/shutdown', '/sbin/halt', '/bin/sync']
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.2
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - no_shelllogin_for_systemaccounts
  - restrict_strategy

Rule   Enforce Usage of pam_wheel with Group Parameter for su Authentication   [ref]

To ensure that only users who are members of the group set in the group option of pam_wheel.so module can run commands with altered privileges through the su command, make sure that the following line exists in the file /etc/pam.d/su:
auth required pam_wheel.so use_uid group=sugroup
         
Warning:  Note that ensure_pam_wheel_group_empty rule complements this requirement by ensuring the referenced group exists and has no members.
Rationale:
The su program allows to run commands with a substitute user and group ID. It is commonly used to run commands as the root user. Limiting access to such command is considered a good security practice.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_use_pam_wheel_group_for_su
References:
cis4.3.6
pcidss42.2.6, 2.2

Rule   Ensure All Groups on the System Have Unique Group ID   [ref]

Change the group name or delete groups, so each has a unique id.
Warning:  Automatic remediation of this control is not available due to the unique requirements of each system.
Rationale:
To assure accountability and prevent unauthenticated access, groups must be identified uniquely to prevent potential misuse and compromise of the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_group_unique_id
References:
disaCCI-000764
os-srgSRG-OS-000104-GPOS-00051
cis6.2.5
pcidss48.2.1, 8.2

Rule   Ensure All Groups on the System Have Unique Group Names   [ref]

Change the group name or delete groups, so each has a unique name.
Warning:  Automatic remediation of this control is not available due to the unique requirements of each system.
Rationale:
To assure accountability and prevent unauthenticated access, groups must be identified uniquely to prevent potential misuse and compromise of the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_group_unique_name
References:
cis6.2.7
pcidss48.2.1, 8.2
Group   Secure Session Configuration Files for Login Accounts   Group contains 2 groups and 14 rules
[ref]   When a user logs into a Unix account, the system configures the user's session by reading a number of files. Many of these files are located in the user's home directory, and may have weak permissions as a result of user error or misconfiguration. If an attacker can modify or even read certain types of account configuration information, they can often gain full access to the affected user's account. Therefore, it is important to test and correct configuration file permissions for interactive accounts, particularly those of privileged users such as root or system administrators.
Group   Ensure that No Dangerous Directories Exist in Root's Path   Group contains 2 rules
[ref]   The active path of the root account can be obtained by starting a new root shell and running:
# echo $PATH
This will produce a colon-separated list of directories in the path.

Certain path elements could be considered dangerous, as they could lead to root executing unknown or untrusted programs, which could contain malicious code. Since root may sometimes work inside untrusted directories, the . character, which represents the current directory, should never be in the root path, nor should any directory which can be written to by an unprivileged or semi-privileged (system) user.

It is a good practice for administrators to always execute privileged commands by typing the full path to the command.

Rule   Ensure that Root's Path Does Not Include World or Group-Writable Directories   [ref]

For each element in root's path, run:
# ls -ld DIR
         
and ensure that write permissions are disabled for group and other.
Rationale:
Such entries increase the risk that root could execute code provided by unprivileged users, and potentially malicious code.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_root_path_dirs_no_write
References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
disaCCI-000366
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-6(a), CM-6(a)
nist-csfPR.IP-1
cis6.2.8

Rule   Ensure that Root's Path Does Not Include Relative Paths or Null Directories   [ref]

Ensure that none of the directories in root's path is equal to a single . character, or that it contains any instances that lead to relative path traversal, such as .. or beginning a path without the slash (/) character. Also ensure that there are no "empty" elements in the path, such as in these examples:
PATH=:/bin
PATH=/bin:
PATH=/bin::/sbin
These empty elements have the same effect as a single . character.
Rationale:
Including these entries increases the risk that root could execute code from an untrusted location.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_root_path_no_dot
References:
cis-csc11, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05
disaCCI-000366
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-6(a), CM-6(a)
nist-csfPR.IP-1
cis6.2.8
Group   Ensure that Users Have Sensible Umask Values   Group contains 3 rules
[ref]   The umask setting controls the default permissions for the creation of new files. With a default umask setting of 077, files and directories created by users will not be readable by any other user on the system. Users who wish to make specific files group- or world-readable can accomplish this by using the chmod command. Additionally, users can make all their files readable to their group by default by setting a umask of 027 in their shell configuration files. If default per-user groups exist (that is, if every user has a default group whose name is the same as that user's username and whose only member is the user), then it may even be safe for users to select a umask of 007, making it very easy to intentionally share files with groups of which the user is a member.

Rule   Ensure the Default Bash Umask is Set Correctly   [ref]

To ensure the default umask for users of the Bash shell is set properly, add or correct the umask setting in /etc/bashrc to read as follows:
umask 027
         
Rationale:
The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_umask_etc_bashrc
References:
cis-csc18
cobit5APO13.01, BAI03.01, BAI03.02, BAI03.03
disaCCI-000366
isa-62443-20094.3.4.3.3
iso27001-2013A.14.1.1, A.14.2.1, A.14.2.5, A.6.1.5
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(1), CM-6(a)
nist-csfPR.IP-2
os-srgSRG-OS-000480-GPOS-00228, SRG-OS-000480-GPOS-00227
anssiR36
cis4.6.5

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

var_accounts_user_umask='027'






grep -q "^[^#]*\bumask" /etc/bashrc && \
  sed -i -E -e "s/^([^#]*\bumask)[[:space:]]+[[:digit:]]+/\1 $var_accounts_user_umask/g" /etc/bashrc
if ! [ $? -eq 0 ]; then
    echo "umask $var_accounts_user_umask" >> /etc/bashrc
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_accounts_user_umask # promote to variable
  set_fact:
    var_accounts_user_umask: !!str 027
  tags:
    - always

- name: Check if umask in /etc/bashrc is already set
  ansible.builtin.lineinfile:
    path: /etc/bashrc
    regexp: ^[^#]*\bumask\s+\d+$
    state: absent
  check_mode: true
  changed_when: false
  register: umask_replace
  when: '"bash" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Replace user umask in /etc/bashrc
  ansible.builtin.replace:
    path: /etc/bashrc
    regexp: ^([^#]*\b)umask\s+\d+$
    replace: \g<1>umask {{ var_accounts_user_umask }}
  when:
  - '"bash" in ansible_facts.packages'
  - umask_replace.found > 0
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure the Default umask is Appended Correctly
  ansible.builtin.lineinfile:
    create: true
    path: /etc/bashrc
    line: umask {{ var_accounts_user_umask }}
  when:
  - '"bash" in ansible_facts.packages'
  - umask_replace.found == 0
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure the Default Umask is Set Correctly in /etc/profile   [ref]

To ensure the default umask controlled by /etc/profile is set properly, add or correct the umask setting in /etc/profile to read as follows:
umask 027
         
Note that /etc/profile also reads scrips within /etc/profile.d directory. These scripts are also valid files to set umask value. Therefore, they should also be considered during the check and properly remediated, if necessary.
Rationale:
The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_umask_etc_profile
References:
cis-csc18
cobit5APO13.01, BAI03.01, BAI03.02, BAI03.03
disaCCI-000366
isa-62443-20094.3.4.3.3
iso27001-2013A.14.1.1, A.14.2.1, A.14.2.5, A.6.1.5
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(1), CM-6(a)
nist-csfPR.IP-2
os-srgSRG-OS-000480-GPOS-00228, SRG-OS-000480-GPOS-00227
anssiR36
cis4.6.5

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

var_accounts_user_umask='027'


readarray -t profile_files < <(find /etc/profile.d/ -type f -name '*.sh' -or -name 'sh.local')

for file in "${profile_files[@]}" /etc/profile; do
  grep -qE '^[^#]*umask' "$file" && sed -i -E "s/^(\s*umask\s*)[0-7]+/\1$var_accounts_user_umask/g" "$file"
done

if ! grep -qrE '^[^#]*umask' /etc/profile*; then
  echo "umask $var_accounts_user_umask" >> /etc/profile
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value var_accounts_user_umask # promote to variable
  set_fact:
    var_accounts_user_umask: !!str 027
  tags:
    - always

- name: Ensure the Default Umask is Set Correctly in /etc/profile - Locate Profile
    Configuration Files Where umask Is Defined
  ansible.builtin.find:
    paths:
    - /etc/profile.d
    patterns:
    - sh.local
    - '*.sh'
    contains: ^[\s]*umask\s+\d+
  register: result_profile_d_files
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure the Default Umask is Set Correctly in /etc/profile - Replace Existing
    umask Value in Files From /etc/profile.d
  ansible.builtin.replace:
    path: '{{ item.path }}'
    regexp: ^(\s*)umask\s+\d+
    replace: \1umask {{ var_accounts_user_umask }}
  loop: '{{ result_profile_d_files.files }}'
  register: result_umask_replaced_profile_d
  when: result_profile_d_files.matched
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure the Default Umask is Set Correctly in /etc/profile - Ensure umask Is
    Set in /etc/profile if Not Already Set Elsewhere
  ansible.builtin.lineinfile:
    create: true
    mode: 420
    path: /etc/profile
    line: umask {{ var_accounts_user_umask }}
  when: not result_profile_d_files.matched
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure the Default Umask is Set Correctly in /etc/profile - Ensure umask Value
    For All Existing umask Definition in /etc/profile
  ansible.builtin.replace:
    path: /etc/profile
    regexp: ^(\s*)umask\s+\d+
    replace: \1umask {{ var_accounts_user_umask }}
  register: result_umask_replaced_profile
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Set Interactive Session Timeout   [ref]

Setting the TMOUT option in /etc/profile ensures that all user sessions will terminate based on inactivity. The value of TMOUT should be exported and read only. The TMOUT setting in a file loaded by /etc/profile, e.g. /etc/profile.d/tmout.sh should read as follows:
typeset -xr TMOUT=900
        
or
declare -xr TMOUT=900
        
Using the typeset keyword is preferred for wider compatibility with ksh and other shells.
Rationale:
Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_tmout
References:
cis-csc1, 12, 15, 16
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.11
disaCCI-000057, CCI-001133
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
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-12, SC-10, AC-2(5), CM-6(a)
nist-csfPR.AC-7
os-srgSRG-OS-000163-GPOS-00072, SRG-OS-000029-GPOS-00010
anssiR32
cis4.6.3
pcidss48.6.1, 8.6

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

var_accounts_tmout='900'


# if 0, no occurence of tmout found, if 1, occurence found
tmout_found=0


for f in /etc/profile /etc/profile.d/*.sh; do

    if grep --silent '^[^#].*TMOUT' $f; then
        sed -i -E "s/^(.*)TMOUT\s*=\s*(\w|\$)*(.*)$/typeset -xr TMOUT=$var_accounts_tmout\3/g" $f
        tmout_found=1
    fi
done

if [ $tmout_found -eq 0 ]; then
        echo -e "\n# Set TMOUT to $var_accounts_tmout per security requirements" >> /etc/profile.d/tmout.sh
        echo "typeset -xr TMOUT=$var_accounts_tmout" >> /etc/profile.d/tmout.sh
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSSv4-8.6
  - PCI-DSSv4-8.6.1
  - accounts_tmout
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_accounts_tmout # promote to variable
  set_fact:
    var_accounts_tmout: !!str 900
  tags:
    - always

- name: Correct any occurrence of TMOUT in /etc/profile
  replace:
    path: /etc/profile
    regexp: ^[^#].*TMOUT=.*
    replace: typeset -xr TMOUT={{ var_accounts_tmout }}
  register: profile_replaced
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSSv4-8.6
  - PCI-DSSv4-8.6.1
  - accounts_tmout
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Interactive Session Timeout
  lineinfile:
    path: /etc/profile.d/tmout.sh
    create: true
    regexp: TMOUT=
    line: typeset -xr TMOUT={{ var_accounts_tmout }}
    state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSSv4-8.6
  - PCI-DSSv4-8.6.1
  - accounts_tmout
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   User Initialization Files Must Be Group-Owned By The Primary Group   [ref]

Change the group owner of interactive users files to the group found in
/etc/passwd
for the user. To change the group owner of a local interactive user home directory, use the following command:
$ sudo chgrp USER_GROUP /home/USER/.INIT_FILE
        
This rule ensures every initialization file related to an interactive user is group-owned by an interactive user.
Warning:  Due to OVAL limitation, this rule can report a false negative in a specific situation where two interactive users swap the group-ownership of their respective initialization files.
Rationale:
Local initialization files for interactive users are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_user_dot_group_ownership
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.2.11

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chgrp -f " $4" "$6"/.[^\.]?*") }' /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Ensure interactive local users are the group-owners of their respective initialization
    files
  ansible.builtin.command:
    cmd: awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chgrp -f " $4" "$6"/.[^\.]?*")
      }' /etc/passwd
  tags:
  - accounts_user_dot_group_ownership
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   User Initialization Files Must Be Owned By the Primary User   [ref]

Set the owner of the user initialization files for interactive users to the primary owner with the following command:
$ sudo chown USER /home/USER/.*
This rule ensures every initialization file related to an interactive user is owned by an interactive user.
Warning:  Due to OVAL limitation, this rule can report a false negative in a specific situation where two interactive users swap the ownership of their respective initialization files.
Rationale:
Local initialization files are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_user_dot_user_ownership
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.2.11

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chown -f " $3" "$6"/.[^\.]?*") }' /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Ensure interactive local users are the owners of their respective initialization
    files
  ansible.builtin.command:
    cmd: awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chown -f " $3" "$6"/.[^\.]?*")
      }' /etc/passwd
  tags:
  - accounts_user_dot_user_ownership
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   All Interactive Users Home Directories Must Exist   [ref]

Create home directories to all local interactive users that currently do not have a home directory assigned. Use the following commands to create the user home directory assigned in /etc/passwd:
$ sudo mkdir /home/USER
        
Rationale:
If a local interactive user has a home directory defined that does not exist, the user may be given access to the / directory as the current working directory upon logon. This could create a Denial of Service because the user would not be able to access their logon configuration files, and it may give them visibility to system files they normally would not be able to access.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_user_interactive_home_directory_exists
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
cis6.2.10

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

for user in $(awk -F':' '{ if ($3 >= 1000 && $3 != 65534) print $1}' /etc/passwd); do
    mkhomedir_helper $user 0077;
done

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - accounts_user_interactive_home_directory_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - accounts_user_interactive_home_directory_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive users have a home directory exists
  ansible.builtin.user:
    name: '{{ item.key }}'
    create_home: true
  loop: '{{ local_users }}'
  when:
  - item.value[2]|int >= 1000
  - item.value[2]|int != 65534
  tags:
  - accounts_user_interactive_home_directory_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure users' .netrc Files are not group or world accessible   [ref]

While the system administrator can establish secure permissions for users' .netrc files, the users can easily override these. This rule ensures every .netrc file or directory under the home directory related to an interactive user is not group or world accessible
Rationale:
.netrc files may contain unencrypted passwords that may be used to attack other systems. Note: While the complete removal of .netrc files is recommended, if any are required on the system, secure permissions must be applied.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_users_netrc_file_permissions
References:
cis6.2.11

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

for user in $(awk -F':' '{ if ($3 >= 1000 && $3 != 65534) print $1 }' /etc/passwd); do
    home_dir=$(getent passwd "$user" | cut -d: -f6)
    find "${home_dir}/.netrc" -exec chmod 0600 {} \;
done

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - accounts_users_netrc_file_permissions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - accounts_users_netrc_file_permissions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Test for existence of .netrc file in home directories to avoid creating them,
    but only fixing permissions
  ansible.builtin.stat:
    path: '{{ item.value[4] }}/.netrc'
  register: path_exists
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int >= 1000
  - item.value[1]|int != 65534
  tags:
  - accounts_users_netrc_file_permissions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure group and world cannot access respective .netrc files
  ansible.builtin.file:
    path: '{{ item.item.value[4] }}/.netrc'
    mode: '0600'
    state: file
  loop: '{{ path_exists.results }}'
  when: item.stat is defined and item.stat.exists
  tags:
  - accounts_users_netrc_file_permissions
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   All Interactive User Home Directories Must Be Group-Owned By The Primary Group   [ref]

Change the group owner of interactive users home directory to the group found in /etc/passwd. To change the group owner of interactive users home directory, use the following command:
$ sudo chgrp USER_GROUP /home/USER
        
This rule ensures every home directory related to an interactive user is group-owned by an interactive user. It also ensures that interactive users are group-owners of one and only one home directory.
Warning:  Due to OVAL limitation, this rule can report a false negative in a specific situation where two interactive users swap the group-ownership of their respective home directories.
Rationale:
If the Group Identifier (GID) of a local interactive users home directory is not the same as the primary GID of the user, this would allow unauthorized access to the users files, and users that share the same group may not be able to access files that they legitimately should.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupownership_home_directories
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
cis6.2.10

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chgrp -f " $4" "$6) }' /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - file_groupownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - file_groupownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Test for existence of home directories to avoid creating them, but only fixing
    group ownership
  ansible.builtin.stat:
    path: '{{ item.value[4] }}'
  register: path_exists
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int >= 1000
  - item.value[1]|int != 65534
  tags:
  - file_groupownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive local users are the group-owners of their respective home
    directories
  ansible.builtin.file:
    path: '{{ item.0.value[4] }}'
    group: '{{ item.0.value[2] }}'
  loop: '{{ local_users|zip(path_exists.results)|list }}'
  when: item.1.stat is defined and item.1.stat.exists
  tags:
  - file_groupownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   All Interactive User Home Directories Must Be Owned By The Primary User   [ref]

Change the owner of interactive users home directories to that correct owner. To change the owner of a interactive users home directory, use the following command:
$ sudo chown USER /home/USER
        
This rule ensures every home directory related to an interactive user is owned by an interactive user. It also ensures that interactive users are owners of one and only one home directory.
Warning:  Due to OVAL limitation, this rule can report a false negative in a specific situation where two interactive users swap the ownership of their respective home directories.
Rationale:
If a local interactive user does not own their home directory, unauthorized users could access or modify the user's files, and the users may not be able to access their own files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_ownership_home_directories
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
cis6.2.10

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chown -f " $3" "$6) }' /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Test for existence of home directories to avoid creating them, but only fixing
    ownership
  ansible.builtin.stat:
    path: '{{ item.value[4] }}'
  register: path_exists
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int >= 1000
  - item.value[1]|int != 65534
  tags:
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive local users are the owners of their respective home directories
  ansible.builtin.file:
    path: '{{ item.0.value[4] }}'
    owner: '{{ item.0.value[1] }}'
  loop: '{{ local_users|zip(path_exists.results)|list }}'
  when: item.1.stat is defined and item.1.stat.exists
  tags:
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure All User Initialization Files Have Mode 0740 Or Less Permissive   [ref]

Set the mode of the user initialization files to 0740 with the following command:
$ sudo chmod 0740 /home/USER/.INIT_FILE
        
Rationale:
Local initialization files are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permission_user_init_files
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.2.11

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

var_user_initialization_files_regex='^\.[\w\- ]+$'


readarray -t interactive_users < <(awk -F: '$3>=1000   {print $1}' /etc/passwd)
readarray -t interactive_users_home < <(awk -F: '$3>=1000   {print $6}' /etc/passwd)
readarray -t interactive_users_shell < <(awk -F: '$3>=1000   {print $7}' /etc/passwd)

USERS_IGNORED_REGEX='nobody|nfsnobody'

for (( i=0; i<"${#interactive_users[@]}"; i++ )); do
    if ! grep -qP "$USERS_IGNORED_REGEX" <<< "${interactive_users[$i]}" && \
        [ "${interactive_users_shell[$i]}" != "/sbin/nologin" ]; then
        
        readarray -t init_files < <(find "${interactive_users_home[$i]}" -maxdepth 1 \
            -exec basename {} \; | grep -P "$var_user_initialization_files_regex")
        for file in "${init_files[@]}"; do
            chmod u-s,g-wxs,o= "${interactive_users_home[$i]}/$file"
        done
    fi
done

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: XCCDF Value var_user_initialization_files_regex # promote to variable
  set_fact:
    var_user_initialization_files_regex: !!str ^\.[\w\- ]+$
  tags:
    - always

- name: Ensure All User Initialization Files Have Mode 0740 Or Less Permissive - Gather
    User Info
  ansible.builtin.getent:
    database: passwd
  tags:
  - file_permission_user_init_files
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure All User Initialization Files Have Mode 0740 Or Less Permissive - Find
    Init Files
  ansible.builtin.find:
    paths: '{{ item.value[4] }}'
    pattern: '{{ var_user_initialization_files_regex }}'
    hidden: true
    use_regex: true
  with_dict: '{{ ansible_facts.getent_passwd }}'
  when:
  - item.value[4] != "/sbin/nologin"
  - item.key not in ["nobody", "nfsnobody"]
  - item.value[1] | int >= 1000
  register: found_init_files
  tags:
  - file_permission_user_init_files
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure All User Initialization Files Have Mode 0740 Or Less Permissive - Fix
    Init Files Permissions
  ansible.builtin.file:
    path: '{{ item.1.path }}'
    mode: u-s,g-wxs,o=
  loop: '{{ q(''ansible.builtin.subelements'', found_init_files.results, ''files'',
    {''skip_missing'': True}) }}'
  tags:
  - file_permission_user_init_files
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   All Interactive User Home Directories Must Have mode 0750 Or Less Permissive   [ref]

Change the mode of interactive users home directories to 0750. To change the mode of interactive users home directory, use the following command:
$ sudo chmod 0750 /home/USER
        
Rationale:
Excessive permissions on local interactive user home directories may allow unauthorized access to user files by other users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_home_directories
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00227
cis6.2.10

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict

for home_dir in $(awk -F':' '{ if ($3 >= 1000 && $3 != 65534 && $6 != "/") print $6 }' /etc/passwd); do
    # Only update the permissions when necessary. This will avoid changing the inode timestamp when
    # the permission is already defined as expected, therefore not impacting in possible integrity
    # check systems that also check inodes timestamps.
    find "$home_dir" -maxdepth 0 -perm /7027 \! -type l -exec chmod u-s,g-w-s,o=- {} \;
done

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Test for existence home directories to avoid creating them.
  ansible.builtin.stat:
    path: '{{ item.value[4] }}'
  register: path_exists
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int >= 1000
  - item.value[1]|int != 65534
  - item.value[4] != "/"
  tags:
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive local users have proper permissions on their respective
    home directories
  ansible.builtin.file:
    path: '{{ item.0.value[4] }}'
    mode: u-s,g-w-s,o=-
    follow: false
    recurse: false
  loop: '{{ local_users|zip(path_exists.results)|list }}'
  when: item.1.stat is defined and item.1.stat.exists
  tags:
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
Group   GRUB2 bootloader configuration   Group contains 1 group and 6 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 Amazon Linux 2023 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 6 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
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-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
nistCM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
pcidssReq-7.1
os-srgSRG-OS-000480-GPOS-00227
anssiR29
cis1.4.1
pcidss42.2.6, 2.2

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 && { rpm --quiet -q kernel; }; then

chgrp 0 /boot/grub2/grub.cfg

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - 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
  - 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'
  - '"kernel" in ansible_facts.packages'
  tags:
  - 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
  - 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'
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

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

The file /boot/grub2/user.cfg should be group-owned by the root group to prevent reading or modification of the file. To properly set the group owner of /boot/grub2/user.cfg, run the command:
$ sudo chgrp root /boot/grub2/user.cfg
Rationale:
The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway. Non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_user_cfg
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
cis1.4.1
pcidss42.2.6, 2.2

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/user.cfg

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/user.cfg
  stat:
    path: /boot/grub2/user.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:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /boot/grub2/user.cfg
  file:
    path: /boot/grub2/user.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:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

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
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-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
nistCM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
pcidssReq-7.1
os-srgSRG-OS-000480-GPOS-00227
anssiR29
cis1.4.1
pcidss42.2.6, 2.2

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 && { rpm --quiet -q kernel; }; then

chown 0 /boot/grub2/grub.cfg

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - 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
  - 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'
  - '"kernel" in ansible_facts.packages'
  tags:
  - 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
  - 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'
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

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

The file /boot/grub2/user.cfg should be owned by the root user to prevent reading or modification of the file. To properly set the owner of /boot/grub2/user.cfg, run the command:
$ sudo chown root /boot/grub2/user.cfg 
Rationale:
Only root should be able to modify important boot parameters. Also, non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_user_cfg
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
anssiR29
cis1.4.1
pcidss42.2.6, 2.2

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/user.cfg

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/user.cfg
  stat:
    path: /boot/grub2/user.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:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /boot/grub2/user.cfg
  file:
    path: /boot/grub2/user.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:
  - 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
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify /boot/grub2/grub.cfg Permissions   [ref]

File permissions for /boot/grub2/grub.cfg should be set to 600. To properly set the permissions of /boot/grub2/grub.cfg, run the command:
$ sudo chmod 600 /boot/grub2/grub.cfg
Rationale:
Proper permissions ensure that only the root user can modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_grub2_cfg
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
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
anssiR29
cis1.4.1
pcidss42.2.6, 2.2

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 && { rpm --quiet -q kernel; }; then

chmod u-xs,g-xwrs,o-xwrt /boot/grub2/grub.cfg

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_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'
  - '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /boot/grub2/grub.cfg
  file:
    path: /boot/grub2/grub.cfg
    mode: u-xs,g-xwrs,o-xwrt
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify /boot/grub2/user.cfg Permissions   [ref]

File permissions for /boot/grub2/user.cfg should be set to 600. To properly set the permissions of /boot/grub2/user.cfg, run the command:
$ sudo chmod 600 /boot/grub2/user.cfg
Rationale:
Proper permissions ensure that only the root user can read or modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_user_cfg
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
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
anssiR29
cis1.4.1
pcidss42.2.6, 2.2

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

chmod u-xs,g-xwrs,o-xwrt /boot/grub2/user.cfg

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/user.cfg
  stat:
    path: /boot/grub2/user.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:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /boot/grub2/user.cfg
  file:
    path: /boot/grub2/user.cfg
    mode: u-xs,g-xwrs,o-xwrt
  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:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
Group   Configure Syslog   Group contains 4 groups and 12 rules
[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 Amazon Linux 2023, 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   Ensure Proper Configuration of Log Files   Group contains 3 rules
[ref]   The file /etc/rsyslog.conf controls where log message are written. These are controlled by lines called rules, which consist of a selector and an action. These rules are often customized depending on the role of the system, the requirements of the environment, and whatever may enable the administrator to most effectively make use of log data. The default rules in Amazon Linux 2023 are:
*.info;mail.none;authpriv.none;cron.none                /var/log/messages
authpriv.*                                              /var/log/secure
mail.*                                                  -/var/log/maillog
cron.*                                                  /var/log/cron
*.emerg                                                 *
uucp,news.crit                                          /var/log/spooler
local7.*                                                /var/log/boot.log
See the man page rsyslog.conf(5) for more information. Note that the rsyslog daemon can be configured to use a timestamp format that some log processing programs may not understand. If this occurs, edit the file /etc/rsyslog.conf and add or edit the following line:
$ ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat

Rule   Ensure Log Files Are Owned By Appropriate Group   [ref]

The group-owner of all log files written by rsyslog should be root. These log files are determined by the second part of each Rule line in /etc/rsyslog.conf and typically all appear in /var/log. For each log file LOGFILE referenced in /etc/rsyslog.conf, run the following command to inspect the file's group owner:
$ ls -l LOGFILE
        
If the owner is not root, run the following command to correct this:
$ sudo chgrp root LOGFILE
        
Rationale:
The log files generated by rsyslog contain valuable information regarding system configuration, user authentication, and other such information. Log files should be protected from unauthorized access.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_files_groupownership
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-001314
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
ism0988, 1405
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
pcidssReq-10.5.1, Req-10.5.2
anssiR71
cis5.1.3
pcidss410.3.2, 10.3

# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel && rpm --quiet -q rsyslog; then

# List of log file paths to be inspected for correct permissions
# * Primarily inspect log file paths listed in /etc/rsyslog.conf
RSYSLOG_ETC_CONFIG="/etc/rsyslog.conf"
# * And also the log file paths listed after rsyslog's $IncludeConfig directive
#   (store the result into array for the case there's shell glob used as value of IncludeConfig)
readarray -t OLD_INC < <(grep -e "\$IncludeConfig[[:space:]]\+[^[:space:];]\+" /etc/rsyslog.conf | cut -d ' ' -f 2)
readarray -t RSYSLOG_INCLUDE_CONFIG < <(for INCPATH in "${OLD_INC[@]}"; do eval printf '%s\\n' "${INCPATH}"; done)
readarray -t NEW_INC < <(sed -n '/^\s*include(/,/)/Ip' /etc/rsyslog.conf | sed -n 's@.*file\s*=\s*"\([/[:alnum:][:punct:]]*\)".*@\1@Ip')
readarray -t RSYSLOG_INCLUDE < <(for INCPATH in "${NEW_INC[@]}"; do eval printf '%s\\n' "${INCPATH}"; done)

# Declare an array to hold the final list of different log file paths
declare -a LOG_FILE_PATHS

# Array to hold all rsyslog config entries
RSYSLOG_CONFIGS=()
RSYSLOG_CONFIGS=("${RSYSLOG_ETC_CONFIG}" "${RSYSLOG_INCLUDE_CONFIG[@]}" "${RSYSLOG_INCLUDE[@]}")

# Get full list of files to be checked
# RSYSLOG_CONFIGS may contain globs such as
# /etc/rsyslog.d/*.conf /etc/rsyslog.d/*.frule
# So, loop over the entries in RSYSLOG_CONFIGS and use find to get the list of included files.
RSYSLOG_CONFIG_FILES=()
for ENTRY in "${RSYSLOG_CONFIGS[@]}"
do
	# If directory, rsyslog will search for config files in recursively.
	# However, files in hidden sub-directories or hidden files will be ignored.
	if [ -d "${ENTRY}" ]
	then
		readarray -t FINDOUT < <(find "${ENTRY}" -not -path '*/.*' -type f)
		RSYSLOG_CONFIG_FILES+=("${FINDOUT[@]}")
	elif [ -f "${ENTRY}" ]
	then
		RSYSLOG_CONFIG_FILES+=("${ENTRY}")
	else
		echo "Invalid include object: ${ENTRY}"
	fi
done

# Browse each file selected above as containing paths of log files
# ('/etc/rsyslog.conf' and '/etc/rsyslog.d/*.conf' in the default configuration)
for LOG_FILE in "${RSYSLOG_CONFIG_FILES[@]}"
do
	# From each of these files extract just particular log file path(s), thus:
	# * Ignore lines starting with space (' '), comment ('#"), or variable syntax ('$') characters,
	# * Ignore empty lines,
	# * Strip quotes and closing brackets from paths.
	# * Ignore paths that match /dev|/etc.*\.conf, as those are paths, but likely not log files
	# * From the remaining valid rows select only fields constituting a log file path
	# Text file column is understood to represent a log file path if and only if all of the
	# following are met:
	# * it contains at least one slash '/' character,
	# * it is preceded by space
	# * it doesn't contain space (' '), colon (':'), and semicolon (';') characters
	# Search log file for path(s) only in case it exists!
	if [[ -f "${LOG_FILE}" ]]
	then
		NORMALIZED_CONFIG_FILE_LINES=$(sed -e "/^[#|$]/d" "${LOG_FILE}")
		LINES_WITH_PATHS=$(grep '[^/]*\s\+\S*/\S\+$' <<< "${NORMALIZED_CONFIG_FILE_LINES}")
		FILTERED_PATHS=$(awk '{if(NF>=2&&($NF~/^\//||$NF~/^-\//)){sub(/^-\//,"/",$NF);print $NF}}' <<< "${LINES_WITH_PATHS}")
		CLEANED_PATHS=$(sed -e "s/[\"')]//g; /\\/etc.*\.conf/d; /\\/dev\\//d" <<< "${FILTERED_PATHS}")
		MATCHED_ITEMS=$(sed -e "/^$/d" <<< "${CLEANED_PATHS}")
		# Since above sed command might return more than one item (delimited by newline), split
		# the particular matches entries into new array specific for this log file
		readarray -t ARRAY_FOR_LOG_FILE <<< "$MATCHED_ITEMS"
		# Concatenate the two arrays - previous content of $LOG_FILE_PATHS array with
		# items from newly created array for this log file
		LOG_FILE_PATHS+=("${ARRAY_FOR_LOG_FILE[@]}")
		# Delete the temporary array
		unset ARRAY_FOR_LOG_FILE
	fi
done

# Check for RainerScript action log format which might be also multiline so grep regex is a bit
# curly:
# extract possibly multiline action omfile expressions
# extract File="logfile" expression
# match only "logfile" expression
for LOG_FILE in "${RSYSLOG_CONFIG_FILES[@]}"
do
	ACTION_OMFILE_LINES=$(grep -iozP "action\s*\(\s*type\s*=\s*\"omfile\"[^\)]*\)" "${LOG_FILE}")
	OMFILE_LINES=$(echo "${ACTION_OMFILE_LINES}"| grep -iaoP "\bFile\s*=\s*\"([/[:alnum:][:punct:]]*)\"\s*\)")
	LOG_FILE_PATHS+=("$(echo "${OMFILE_LINES}"| grep -oE "\"([/[:alnum:][:punct:]]*)\""|tr -d "\"")")
done

# Ensure the correct attribute if file exists
FILE_CMD="chgrp"
for LOG_FILE_PATH in "${LOG_FILE_PATHS[@]}"
do
	# Sanity check - if particular $LOG_FILE_PATH is empty string, skip it from further processing
	if [ -z "$LOG_FILE_PATH" ]
	then
		continue
	fi
	$FILE_CMD "root" "$LOG_FILE_PATH"
done

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

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Set rsyslog logfile configuration
    facts
  ansible.builtin.set_fact:
    rsyslog_etc_config: /etc/rsyslog.conf
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Get IncludeConfig directive
  ansible.builtin.shell: |
    set -o pipefail
    grep -e '$IncludeConfig' {{ rsyslog_etc_config }} | cut -d ' ' -f 2 || true
  register: rsyslog_old_inc
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Get include files directives
  ansible.builtin.shell: |
    set -o pipefail
    awk '/)/{f=0} /include\(/{f=1} f{ nf=gensub("^(include\\(|\\s*)file=\"(\\S+)\".*","\\2",1); if($0!=nf){ print nf }}' {{ rsyslog_etc_config }} || true
  register: rsyslog_new_inc
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Aggregate rsyslog includes
  ansible.builtin.set_fact:
    include_config_output: '{{ rsyslog_old_inc.stdout_lines + rsyslog_new_inc.stdout_lines
      }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_old_inc is not skipped and rsyslog_new_inc is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - List all config files
  ansible.builtin.find:
    paths: '{{ item | dirname }}'
    patterns: '{{ item | basename }}'
    hidden: false
    follow: true
  loop: '{{ include_config_output | list + [rsyslog_etc_config] }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - include_config_output is defined
  register: rsyslog_config_files
  failed_when: false
  changed_when: false
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Extract log files old format
  ansible.builtin.shell: |
    set -o pipefail
    grep -oP '^[^(\s|#|\$)]+[\s]+.*[\s]+-?(/+[^:;\s]+);*\.*$' {{ item.1.path }} | \
    awk '{print $NF}' | \
    sed -e 's/^-//' || true
  loop: '{{ rsyslog_config_files.results | default([]) | subelements(''files'') }}'
  register: log_files_old
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_config_files is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Extract log files new format
  ansible.builtin.shell: |
    set -o pipefail
    grep -ozP "action\s*\(\s*type\s*=\s*\"omfile\"[^\)]*\)" {{ item.1.path }} | \
    grep -aoP "\bFile\s*=\s*\"([/[:alnum:][:punct:]]*)\"\s*\)" | \
    grep -oE "\"([/[:alnum:][:punct:]]*)\"" | \
    tr -d "\""|| true
  loop: '{{ rsyslog_config_files.results | default([]) | subelements(''files'') }}'
  register: log_files_new
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_config_files is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group - Sum all log files found
  ansible.builtin.set_fact:
    log_files: '{{ log_files_new.results | map(attribute=''stdout_lines'') | list
      | flatten | unique + log_files_old.results | map(attribute=''stdout_lines'')
      | list | flatten | unique }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

- name: Ensure Log Files Are Owned By Appropriate Group -Setup log files attribute
  ansible.builtin.file:
    path: '{{ item }}'
    group: root
    state: file
  loop: '{{ log_files | list | flatten | unique }}'
  failed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_groupownership

Rule   Ensure Log Files Are Owned By Appropriate User   [ref]

The owner of all log files written by rsyslog should be root. These log files are determined by the second part of each Rule line in /etc/rsyslog.conf and typically all appear in /var/log. For each log file LOGFILE referenced in /etc/rsyslog.conf, run the following command to inspect the file's owner:
$ ls -l LOGFILE
        
If the owner is not root, run the following command to correct this:
$ sudo chown root LOGFILE
        
Rationale:
The log files generated by rsyslog contain valuable information regarding system configuration, user authentication, and other such information. Log files should be protected from unauthorized access.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_files_ownership
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-001314
isa-62443-20094.3.3.7.3
isa-62443-2013SR 2.1, SR 5.2
ism0988, 1405
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
pcidssReq-10.5.1, Req-10.5.2
anssiR71
cis5.1.3
pcidss410.3.2, 10.3

# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel && rpm --quiet -q rsyslog; then

# List of log file paths to be inspected for correct permissions
# * Primarily inspect log file paths listed in /etc/rsyslog.conf
RSYSLOG_ETC_CONFIG="/etc/rsyslog.conf"
# * And also the log file paths listed after rsyslog's $IncludeConfig directive
#   (store the result into array for the case there's shell glob used as value of IncludeConfig)
readarray -t OLD_INC < <(grep -e "\$IncludeConfig[[:space:]]\+[^[:space:];]\+" /etc/rsyslog.conf | cut -d ' ' -f 2)
readarray -t RSYSLOG_INCLUDE_CONFIG < <(for INCPATH in "${OLD_INC[@]}"; do eval printf '%s\\n' "${INCPATH}"; done)
readarray -t NEW_INC < <(sed -n '/^\s*include(/,/)/Ip' /etc/rsyslog.conf | sed -n 's@.*file\s*=\s*"\([/[:alnum:][:punct:]]*\)".*@\1@Ip')
readarray -t RSYSLOG_INCLUDE < <(for INCPATH in "${NEW_INC[@]}"; do eval printf '%s\\n' "${INCPATH}"; done)

# Declare an array to hold the final list of different log file paths
declare -a LOG_FILE_PATHS

# Array to hold all rsyslog config entries
RSYSLOG_CONFIGS=()
RSYSLOG_CONFIGS=("${RSYSLOG_ETC_CONFIG}" "${RSYSLOG_INCLUDE_CONFIG[@]}" "${RSYSLOG_INCLUDE[@]}")

# Get full list of files to be checked
# RSYSLOG_CONFIGS may contain globs such as
# /etc/rsyslog.d/*.conf /etc/rsyslog.d/*.frule
# So, loop over the entries in RSYSLOG_CONFIGS and use find to get the list of included files.
RSYSLOG_CONFIG_FILES=()
for ENTRY in "${RSYSLOG_CONFIGS[@]}"
do
	# If directory, rsyslog will search for config files in recursively.
	# However, files in hidden sub-directories or hidden files will be ignored.
	if [ -d "${ENTRY}" ]
	then
		readarray -t FINDOUT < <(find "${ENTRY}" -not -path '*/.*' -type f)
		RSYSLOG_CONFIG_FILES+=("${FINDOUT[@]}")
	elif [ -f "${ENTRY}" ]
	then
		RSYSLOG_CONFIG_FILES+=("${ENTRY}")
	else
		echo "Invalid include object: ${ENTRY}"
	fi
done

# Browse each file selected above as containing paths of log files
# ('/etc/rsyslog.conf' and '/etc/rsyslog.d/*.conf' in the default configuration)
for LOG_FILE in "${RSYSLOG_CONFIG_FILES[@]}"
do
	# From each of these files extract just particular log file path(s), thus:
	# * Ignore lines starting with space (' '), comment ('#"), or variable syntax ('$') characters,
	# * Ignore empty lines,
	# * Strip quotes and closing brackets from paths.
	# * Ignore paths that match /dev|/etc.*\.conf, as those are paths, but likely not log files
	# * From the remaining valid rows select only fields constituting a log file path
	# Text file column is understood to represent a log file path if and only if all of the
	# following are met:
	# * it contains at least one slash '/' character,
	# * it is preceded by space
	# * it doesn't contain space (' '), colon (':'), and semicolon (';') characters
	# Search log file for path(s) only in case it exists!
	if [[ -f "${LOG_FILE}" ]]
	then
		NORMALIZED_CONFIG_FILE_LINES=$(sed -e "/^[#|$]/d" "${LOG_FILE}")
		LINES_WITH_PATHS=$(grep '[^/]*\s\+\S*/\S\+$' <<< "${NORMALIZED_CONFIG_FILE_LINES}")
		FILTERED_PATHS=$(awk '{if(NF>=2&&($NF~/^\//||$NF~/^-\//)){sub(/^-\//,"/",$NF);print $NF}}' <<< "${LINES_WITH_PATHS}")
		CLEANED_PATHS=$(sed -e "s/[\"')]//g; /\\/etc.*\.conf/d; /\\/dev\\//d" <<< "${FILTERED_PATHS}")
		MATCHED_ITEMS=$(sed -e "/^$/d" <<< "${CLEANED_PATHS}")
		# Since above sed command might return more than one item (delimited by newline), split
		# the particular matches entries into new array specific for this log file
		readarray -t ARRAY_FOR_LOG_FILE <<< "$MATCHED_ITEMS"
		# Concatenate the two arrays - previous content of $LOG_FILE_PATHS array with
		# items from newly created array for this log file
		LOG_FILE_PATHS+=("${ARRAY_FOR_LOG_FILE[@]}")
		# Delete the temporary array
		unset ARRAY_FOR_LOG_FILE
	fi
done

# Check for RainerScript action log format which might be also multiline so grep regex is a bit
# curly:
# extract possibly multiline action omfile expressions
# extract File="logfile" expression
# match only "logfile" expression
for LOG_FILE in "${RSYSLOG_CONFIG_FILES[@]}"
do
	ACTION_OMFILE_LINES=$(grep -iozP "action\s*\(\s*type\s*=\s*\"omfile\"[^\)]*\)" "${LOG_FILE}")
	OMFILE_LINES=$(echo "${ACTION_OMFILE_LINES}"| grep -iaoP "\bFile\s*=\s*\"([/[:alnum:][:punct:]]*)\"\s*\)")
	LOG_FILE_PATHS+=("$(echo "${OMFILE_LINES}"| grep -oE "\"([/[:alnum:][:punct:]]*)\""|tr -d "\"")")
done

# Ensure the correct attribute if file exists
FILE_CMD="chown"
for LOG_FILE_PATH in "${LOG_FILE_PATHS[@]}"
do
	# Sanity check - if particular $LOG_FILE_PATH is empty string, skip it from further processing
	if [ -z "$LOG_FILE_PATH" ]
	then
		continue
	fi
	$FILE_CMD "root" "$LOG_FILE_PATH"
done

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

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Set rsyslog logfile configuration
    facts
  ansible.builtin.set_fact:
    rsyslog_etc_config: /etc/rsyslog.conf
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Get IncludeConfig directive
  ansible.builtin.shell: |
    set -o pipefail
    grep -e '$IncludeConfig' {{ rsyslog_etc_config }} | cut -d ' ' -f 2 || true
  register: rsyslog_old_inc
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Get include files directives
  ansible.builtin.shell: |
    set -o pipefail
    awk '/)/{f=0} /include\(/{f=1} f{ nf=gensub("^(include\\(|\\s*)file=\"(\\S+)\".*","\\2",1); if($0!=nf){ print nf }}' {{ rsyslog_etc_config }} || true
  register: rsyslog_new_inc
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Aggregate rsyslog includes
  ansible.builtin.set_fact:
    include_config_output: '{{ rsyslog_old_inc.stdout_lines + rsyslog_new_inc.stdout_lines
      }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_old_inc is not skipped and rsyslog_new_inc is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - List all config files
  ansible.builtin.find:
    paths: '{{ item | dirname }}'
    patterns: '{{ item | basename }}'
    hidden: false
    follow: true
  loop: '{{ include_config_output | list + [rsyslog_etc_config] }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - include_config_output is defined
  register: rsyslog_config_files
  failed_when: false
  changed_when: false
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Extract log files old format
  ansible.builtin.shell: |
    set -o pipefail
    grep -oP '^[^(\s|#|\$)]+[\s]+.*[\s]+-?(/+[^:;\s]+);*\.*$' {{ item.1.path }} | \
    awk '{print $NF}' | \
    sed -e 's/^-//' || true
  loop: '{{ rsyslog_config_files.results | default([]) | subelements(''files'') }}'
  register: log_files_old
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_config_files is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Extract log files new format
  ansible.builtin.shell: |
    set -o pipefail
    grep -ozP "action\s*\(\s*type\s*=\s*\"omfile\"[^\)]*\)" {{ item.1.path }} | \
    grep -aoP "\bFile\s*=\s*\"([/[:alnum:][:punct:]]*)\"\s*\)" | \
    grep -oE "\"([/[:alnum:][:punct:]]*)\"" | \
    tr -d "\""|| true
  loop: '{{ rsyslog_config_files.results | default([]) | subelements(''files'') }}'
  register: log_files_new
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_config_files is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User - Sum all log files found
  ansible.builtin.set_fact:
    log_files: '{{ log_files_new.results | map(attribute=''stdout_lines'') | list
      | flatten | unique + log_files_old.results | map(attribute=''stdout_lines'')
      | list | flatten | unique }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

- name: Ensure Log Files Are Owned By Appropriate User -Setup log files attribute
  ansible.builtin.file:
    path: '{{ item }}'
    owner: root
    state: file
  loop: '{{ log_files | list | flatten | unique }}'
  failed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.2
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_ownership

Rule   Ensure System Log Files Have Correct Permissions   [ref]

The file permissions for all log files written by rsyslog should be set to 640, or more restrictive. These log files are determined by the second part of each Rule line in /etc/rsyslog.conf and typically all appear in /var/log. For each log file LOGFILE referenced in /etc/rsyslog.conf, run the following command to inspect the file's permissions:
$ ls -l LOGFILE
        
If the permissions are not 640 or more restrictive, run the following command to correct this:
$ sudo chmod 640 LOGFILE
        
"
Rationale:
Log files can contain valuable information regarding system configuration. If the system log files are not protected unauthorized users could change the logged data, eliminating their forensic value.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_files_permissions
References:
disaCCI-001314
ism0988, 1405
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)
pcidssReq-10.5.1, Req-10.5.2
anssiR71
cis5.1.3
pcidss410.3.1, 10.3

# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel && rpm --quiet -q rsyslog; then

# List of log file paths to be inspected for correct permissions
# * Primarily inspect log file paths listed in /etc/rsyslog.conf
RSYSLOG_ETC_CONFIG="/etc/rsyslog.conf"
# * And also the log file paths listed after rsyslog's $IncludeConfig directive
#   (store the result into array for the case there's shell glob used as value of IncludeConfig)
readarray -t OLD_INC < <(grep -e "\$IncludeConfig[[:space:]]\+[^[:space:];]\+" /etc/rsyslog.conf | cut -d ' ' -f 2)
readarray -t RSYSLOG_INCLUDE_CONFIG < <(for INCPATH in "${OLD_INC[@]}"; do eval printf '%s\\n' "${INCPATH}"; done)
readarray -t NEW_INC < <(sed -n '/^\s*include(/,/)/Ip' /etc/rsyslog.conf | sed -n 's@.*file\s*=\s*"\([/[:alnum:][:punct:]]*\)".*@\1@Ip')
readarray -t RSYSLOG_INCLUDE < <(for INCPATH in "${NEW_INC[@]}"; do eval printf '%s\\n' "${INCPATH}"; done)

# Declare an array to hold the final list of different log file paths
declare -a LOG_FILE_PATHS

# Array to hold all rsyslog config entries
RSYSLOG_CONFIGS=()
RSYSLOG_CONFIGS=("${RSYSLOG_ETC_CONFIG}" "${RSYSLOG_INCLUDE_CONFIG[@]}" "${RSYSLOG_INCLUDE[@]}")

# Get full list of files to be checked
# RSYSLOG_CONFIGS may contain globs such as
# /etc/rsyslog.d/*.conf /etc/rsyslog.d/*.frule
# So, loop over the entries in RSYSLOG_CONFIGS and use find to get the list of included files.
RSYSLOG_CONFIG_FILES=()
for ENTRY in "${RSYSLOG_CONFIGS[@]}"
do
	# If directory, rsyslog will search for config files in recursively.
	# However, files in hidden sub-directories or hidden files will be ignored.
	if [ -d "${ENTRY}" ]
	then
		readarray -t FINDOUT < <(find "${ENTRY}" -not -path '*/.*' -type f)
		RSYSLOG_CONFIG_FILES+=("${FINDOUT[@]}")
	elif [ -f "${ENTRY}" ]
	then
		RSYSLOG_CONFIG_FILES+=("${ENTRY}")
	else
		echo "Invalid include object: ${ENTRY}"
	fi
done

# Browse each file selected above as containing paths of log files
# ('/etc/rsyslog.conf' and '/etc/rsyslog.d/*.conf' in the default configuration)
for LOG_FILE in "${RSYSLOG_CONFIG_FILES[@]}"
do
	# From each of these files extract just particular log file path(s), thus:
	# * Ignore lines starting with space (' '), comment ('#"), or variable syntax ('$') characters,
	# * Ignore empty lines,
	# * Strip quotes and closing brackets from paths.
	# * Ignore paths that match /dev|/etc.*\.conf, as those are paths, but likely not log files
	# * From the remaining valid rows select only fields constituting a log file path
	# Text file column is understood to represent a log file path if and only if all of the
	# following are met:
	# * it contains at least one slash '/' character,
	# * it is preceded by space
	# * it doesn't contain space (' '), colon (':'), and semicolon (';') characters
	# Search log file for path(s) only in case it exists!
	if [[ -f "${LOG_FILE}" ]]
	then
		NORMALIZED_CONFIG_FILE_LINES=$(sed -e "/^[#|$]/d" "${LOG_FILE}")
		LINES_WITH_PATHS=$(grep '[^/]*\s\+\S*/\S\+$' <<< "${NORMALIZED_CONFIG_FILE_LINES}")
		FILTERED_PATHS=$(awk '{if(NF>=2&&($NF~/^\//||$NF~/^-\//)){sub(/^-\//,"/",$NF);print $NF}}' <<< "${LINES_WITH_PATHS}")
		CLEANED_PATHS=$(sed -e "s/[\"')]//g; /\\/etc.*\.conf/d; /\\/dev\\//d" <<< "${FILTERED_PATHS}")
		MATCHED_ITEMS=$(sed -e "/^$/d" <<< "${CLEANED_PATHS}")
		# Since above sed command might return more than one item (delimited by newline), split
		# the particular matches entries into new array specific for this log file
		readarray -t ARRAY_FOR_LOG_FILE <<< "$MATCHED_ITEMS"
		# Concatenate the two arrays - previous content of $LOG_FILE_PATHS array with
		# items from newly created array for this log file
		LOG_FILE_PATHS+=("${ARRAY_FOR_LOG_FILE[@]}")
		# Delete the temporary array
		unset ARRAY_FOR_LOG_FILE
	fi
done

# Check for RainerScript action log format which might be also multiline so grep regex is a bit
# curly:
# extract possibly multiline action omfile expressions
# extract File="logfile" expression
# match only "logfile" expression
for LOG_FILE in "${RSYSLOG_CONFIG_FILES[@]}"
do
	ACTION_OMFILE_LINES=$(grep -iozP "action\s*\(\s*type\s*=\s*\"omfile\"[^\)]*\)" "${LOG_FILE}")
	OMFILE_LINES=$(echo "${ACTION_OMFILE_LINES}"| grep -iaoP "\bFile\s*=\s*\"([/[:alnum:][:punct:]]*)\"\s*\)")
	LOG_FILE_PATHS+=("$(echo "${OMFILE_LINES}"| grep -oE "\"([/[:alnum:][:punct:]]*)\""|tr -d "\"")")
done

# Ensure the correct attribute if file exists
FILE_CMD="chmod"
for LOG_FILE_PATH in "${LOG_FILE_PATHS[@]}"
do
	# Sanity check - if particular $LOG_FILE_PATH is empty string, skip it from further processing
	if [ -z "$LOG_FILE_PATH" ]
	then
		continue
	fi
	$FILE_CMD "0640" "$LOG_FILE_PATH"
done

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

Complexity:low
Disruption:medium
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Set rsyslog logfile configuration
    facts
  ansible.builtin.set_fact:
    rsyslog_etc_config: /etc/rsyslog.conf
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Get IncludeConfig directive
  ansible.builtin.shell: |
    set -o pipefail
    grep -e '$IncludeConfig' {{ rsyslog_etc_config }} | cut -d ' ' -f 2 || true
  register: rsyslog_old_inc
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Get include files directives
  ansible.builtin.shell: |
    set -o pipefail
    awk '/)/{f=0} /include\(/{f=1} f{ nf=gensub("^(include\\(|\\s*)file=\"(\\S+)\".*","\\2",1); if($0!=nf){ print nf }}' {{ rsyslog_etc_config }} || true
  register: rsyslog_new_inc
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Aggregate rsyslog includes
  ansible.builtin.set_fact:
    include_config_output: '{{ rsyslog_old_inc.stdout_lines + rsyslog_new_inc.stdout_lines
      }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_old_inc is not skipped and rsyslog_new_inc is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - List all config files
  ansible.builtin.find:
    paths: '{{ item | dirname }}'
    patterns: '{{ item | basename }}'
    hidden: false
    follow: true
  loop: '{{ include_config_output | list + [rsyslog_etc_config] }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - include_config_output is defined
  register: rsyslog_config_files
  failed_when: false
  changed_when: false
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Extract log files old format
  ansible.builtin.shell: |
    set -o pipefail
    grep -oP '^[^(\s|#|\$)]+[\s]+.*[\s]+-?(/+[^:;\s]+);*\.*$' {{ item.1.path }} | \
    awk '{print $NF}' | \
    sed -e 's/^-//' || true
  loop: '{{ rsyslog_config_files.results | default([]) | subelements(''files'') }}'
  register: log_files_old
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_config_files is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Extract log files new format
  ansible.builtin.shell: |
    set -o pipefail
    grep -ozP "action\s*\(\s*type\s*=\s*\"omfile\"[^\)]*\)" {{ item.1.path }} | \
    grep -aoP "\bFile\s*=\s*\"([/[:alnum:][:punct:]]*)\"\s*\)" | \
    grep -oE "\"([/[:alnum:][:punct:]]*)\"" | \
    tr -d "\""|| true
  loop: '{{ rsyslog_config_files.results | default([]) | subelements(''files'') }}'
  register: log_files_new
  changed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  - rsyslog_config_files is not skipped
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions - Sum all log files found
  ansible.builtin.set_fact:
    log_files: '{{ log_files_new.results | map(attribute=''stdout_lines'') | list
      | flatten | unique + log_files_old.results | map(attribute=''stdout_lines'')
      | list | flatten | unique }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions

- name: Ensure System Log Files Have Correct Permissions -Setup log files attribute
  ansible.builtin.file:
    path: '{{ item }}'
    mode: '0640'
    state: file
  loop: '{{ log_files | list | flatten | unique }}'
  failed_when: false
  when:
  - '"kernel" in ansible_facts.packages'
  - '"rsyslog" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.5.1
  - PCI-DSS-Req-10.5.2
  - PCI-DSSv4-10.3
  - PCI-DSSv4-10.3.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_files_permissions
Group   systemd-journald   Group contains 5 rules
[ref]   systemd-journald is a system service that collects and stores logging data. It creates and maintains structured, indexed journals based on logging information that is received from a variety of sources. For more information on systemd-journald and additional systemd-journald configuration options, see https://systemd.io/.

Rule   Enable systemd-journald Service   [ref]

The systemd-journald service is an essential component of systemd. The systemd-journald service can be enabled with the following command:
$ sudo systemctl enable systemd-journald.service
Rationale:
In the event of a system failure, Amazon Linux 2023 must preserve any information necessary to determine cause of failure and any information necessary to return to operations with least disruption to system processes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_systemd-journald_enabled
References:
disaCCI-001665
nistSC-24
os-srgSRG-OS-000269-GPOS-00103
cis5.1.2.2


[customizations.services]
enabled = ["systemd-journald"]

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-SC-24
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_systemd-journald_enabled

- name: Enable systemd-journald Service - Enable service systemd-journald
  block:

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

  - name: Enable systemd-journald Service - Enable Service systemd-journald
    ansible.builtin.systemd:
      name: systemd-journald
      enabled: true
      state: started
      masked: false
    when:
    - '"systemd" in ansible_facts.packages'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-SC-24
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_systemd-journald_enabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include enable_systemd-journald

class enable_systemd-journald {
  service {'systemd-journald':
    enable => true,
    ensure => 'running',
  }
}

Rule   Ensure journald is configured to compress large log files   [ref]

The journald system can compress large log files to avoid fill the system disk.
Rationale:
Log files that are not properly compressed run the risk of growing so large that they fill up the log partition. Valuable logging information could be lost if the log partition becomes full.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_compress
References:
cis5.1.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

if [ -e "/etc/systemd/journald.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Compress\s*=\s*/d" "/etc/systemd/journald.conf"
else
    touch "/etc/systemd/journald.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/journald.conf"

cp "/etc/systemd/journald.conf" "/etc/systemd/journald.conf.bak"
# Insert before the line matching the regex '^#\s*Compress'.
line_number="$(LC_ALL=C grep -n "^#\s*Compress" "/etc/systemd/journald.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^#\s*Compress', insert at
    # the end of the file.
    printf '%s\n' "Compress=yes" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "Compress=yes" >> "/etc/systemd/journald.conf"
    tail -n "+$(( line_number ))" "/etc/systemd/journald.conf.bak" >> "/etc/systemd/journald.conf"
fi
# Clean up after ourselves.
rm "/etc/systemd/journald.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - journald_compress
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Setting unquoted shell-style assignment of 'Compress' to 'yes' in '/etc/systemd/journald.conf'
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*Compress=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*Compress=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*Compress=
      line: Compress=yes
      state: present
      insertbefore: ^# Compress
      validate: /usr/bin/bash -n %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - journald_compress
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure journald is configured to send logs to rsyslog   [ref]

Data from journald may be stored in volatile memory or persisted locally. Utilities exist to accept remote export of journald logs.
Rationale:
Storing log data on a remote host protects log integrity from local attacks. If an attacker gains root access on the local system, they could tamper with or remove log data that is stored on the local system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_forward_to_syslog
References:
cis5.1.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

if [ -e "/etc/systemd/journald.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*ForwardToSyslog\s*=\s*/d" "/etc/systemd/journald.conf"
else
    touch "/etc/systemd/journald.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/journald.conf"

cp "/etc/systemd/journald.conf" "/etc/systemd/journald.conf.bak"
# Insert before the line matching the regex '^#\s*ForwardToSyslog'.
line_number="$(LC_ALL=C grep -n "^#\s*ForwardToSyslog" "/etc/systemd/journald.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^#\s*ForwardToSyslog', insert at
    # the end of the file.
    printf '%s\n' "ForwardToSyslog=yes" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "ForwardToSyslog=yes" >> "/etc/systemd/journald.conf"
    tail -n "+$(( line_number ))" "/etc/systemd/journald.conf.bak" >> "/etc/systemd/journald.conf"
fi
# Clean up after ourselves.
rm "/etc/systemd/journald.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - journald_forward_to_syslog
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Setting unquoted shell-style assignment of 'ForwardToSyslog' to 'yes' in '/etc/systemd/journald.conf'
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*ForwardToSyslog=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*ForwardToSyslog=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*ForwardToSyslog=
      line: ForwardToSyslog=yes
      state: present
      insertbefore: ^# ForwardToSyslog
      validate: /usr/bin/bash -n %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - journald_forward_to_syslog
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure journald is configured to write log files to persistent disk   [ref]

The journald system may store log files in volatile memory or locally on disk. If the logs are only stored in volatile memory they will we lost upon reboot.
Rationale:
Log files contain valuable data and need to be persistent to aid in possible investigations.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_storage
References:
cis5.1.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

if [ -e "/etc/systemd/journald.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Storage\s*=\s*/d" "/etc/systemd/journald.conf"
else
    touch "/etc/systemd/journald.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/journald.conf"

cp "/etc/systemd/journald.conf" "/etc/systemd/journald.conf.bak"
# Insert before the line matching the regex '^#\s*Storage'.
line_number="$(LC_ALL=C grep -n "^#\s*Storage" "/etc/systemd/journald.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^#\s*Storage', insert at
    # the end of the file.
    printf '%s\n' "Storage=persistent" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "Storage=persistent" >> "/etc/systemd/journald.conf"
    tail -n "+$(( line_number ))" "/etc/systemd/journald.conf.bak" >> "/etc/systemd/journald.conf"
fi
# Clean up after ourselves.
rm "/etc/systemd/journald.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - journald_storage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Setting unquoted shell-style assignment of 'Storage' to 'persistent' in '/etc/systemd/journald.conf'
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*Storage=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*Storage=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: (?i)^\s*Storage=
      line: Storage=persistent
      state: present
      insertbefore: ^# Storage
      validate: /usr/bin/bash -n %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - journald_storage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Disable systemd-journal-remote Socket   [ref]

Journald supports the ability to receive messages from remote hosts, thus acting as a log server. Clients should not receive data from other hosts. NOTE: The same package, systemd-journal-remote , is used for both sending logs to remote hosts and receiving incoming logs. With regards to receiving logs, there are two Systemd unit files; systemd-journal-remote.socket and systemd-journal-remote.service.
Rationale:
If a client is configured to also receive data, thus turning it into a server, the client system is acting outside it's operational boundary.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_socket_systemd-journal-remote_disabled
References:
cis5.1.2.1.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

SOCKET_NAME="systemd-journal-remote.socket"
SYSTEMCTL_EXEC='/usr/bin/systemctl'

if "$SYSTEMCTL_EXEC" -q list-unit-files --type socket | grep -q "$SOCKET_NAME"; then
    "$SYSTEMCTL_EXEC" stop "$SOCKET_NAME"
    "$SYSTEMCTL_EXEC" mask "$SOCKET_NAME"
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - socket_systemd-journal-remote_disabled

- name: Disable systemd-journal-remote Socket - Collect systemd Socket Units Present
    in the System
  ansible.builtin.command:
    cmd: systemctl -q list-unit-files --type socket
  register: result_systemd_unit_files
  changed_when: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - socket_systemd-journal-remote_disabled

- name: Disable systemd-journal-remote Socket - Ensure systemd-journal-remote.socket
    is Masked
  ansible.builtin.systemd:
    name: systemd-journal-remote.socket
    state: stopped
    enabled: false
    masked: true
  when:
  - '"kernel" in ansible_facts.packages'
  - result_systemd_unit_files.stdout_lines is search("systemd-journal-remote.socket")
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - socket_systemd-journal-remote_disabled
Group   Configure rsyslogd to Accept Remote Messages If Acting as a Log Server   Group contains 1 rule
[ref]   By default, rsyslog does not listen over the network for log messages. If needed, modules can be enabled to allow the rsyslog daemon to receive messages from other systems and for the system thus to act as a log server. If the system is not a log server, then lines concerning these modules should remain commented out.

Rule   Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server   [ref]

The rsyslog daemon should not accept remote messages unless the system acts as a log server. To ensure that it is not listening on the network, ensure any of the following lines are not found in rsyslog configuration files. If using legacy syntax:
$ModLoad imtcp
$InputTCPServerRun port
$ModLoad imudp
$UDPServerRun port
$ModLoad imrelp
$InputRELPServerRun port
        
If using RainerScript syntax:
module(load="imtcp")
module(load="imudp")
input(type="imtcp" port="514")
input(type="imudp" port="514")
Rationale:
Any process which receives messages from the network incurs some risk of receiving malicious messages. This risk can be eliminated for rsyslog by configuring it not to listen on the network.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_nolisten
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 4, 5, 6, 8, 9
cobit5APO01.06, APO11.04, APO13.01, BAI03.05, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.05, DSS03.01, DSS05.02, DSS05.04, DSS05.07, DSS06.02, MEA02.01
disaCCI-000366
isa-62443-20094.2.3.4, 4.3.3.3.9, 4.3.3.4, 4.3.3.5.8, 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, 4.4.3.3
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, 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
ism0988, 1405
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.12.5.1, A.12.6.2, 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.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
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfDE.AE-1, ID.AM-3, PR.AC-5, PR.DS-5, PR.IP-1, PR.PT-1, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
cis5.1.1.7

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

legacy_regex='^\s*\$(((Input(TCP|RELP)|UDP)ServerRun)|ModLoad\s+(imtcp|imudp|imrelp))'
rainer_regex='^\s*(module|input)\((load|type)="(imtcp|imudp)".*$'

readarray -t legacy_targets < <(grep -l -E -r "${legacy_regex[@]}" /etc/rsyslog.conf /etc/rsyslog.d/)
readarray -t rainer_targets < <(grep -l -E -r "${rainer_regex[@]}" /etc/rsyslog.conf /etc/rsyslog.d/)

config_changed=false
if [ ${#legacy_targets[@]} -gt 0 ]; then
    for target in "${legacy_targets[@]}"; do
        sed -E -i "/$legacy_regex/ s/^/# /" "$target"
    done
    config_changed=true
fi

if [ ${#rainer_targets[@]} -gt 0 ]; then
    for target in "${rainer_targets[@]}"; do
        sed -E -i "/$rainer_regex/ s/^/# /" "$target"
    done
    config_changed=true
fi

if $config_changed; then
    systemctl restart rsyslog.service
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Define Rsyslog Config Lines Regex in Legacy Syntax
  ansible.builtin.set_fact:
    rsyslog_listen_legacy_regex: ^\s*\$(((Input(TCP|RELP)|UDP)ServerRun)|ModLoad\s+(imtcp|imudp|imrelp))
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Search for Legacy Config Lines in Rsyslog Main Config File
  ansible.builtin.find:
    paths: /etc
    pattern: rsyslog.conf
    contains: '{{ rsyslog_listen_legacy_regex }}'
  register: rsyslog_listen_legacy_main_file
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Search for Legacy Config Lines in Rsyslog Include Files
  ansible.builtin.find:
    paths: /etc/rsyslog.d/
    pattern: '*.conf'
    contains: '{{ rsyslog_listen_legacy_regex }}'
  register: rsyslog_listen_legacy_include_files
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Assemble List of Config Files With Listen Lines in Legacy Syntax
  ansible.builtin.set_fact:
    rsyslog_legacy_remote_listen_files: '{{ rsyslog_listen_legacy_main_file.files
      | map(attribute=''path'') | list + rsyslog_listen_legacy_include_files.files
      | map(attribute=''path'') | list }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Comment Listen Config Lines Wherever Defined Using Legacy Syntax
  ansible.builtin.replace:
    path: '{{ item }}'
    regexp: '{{ rsyslog_listen_legacy_regex }}'
    replace: '# \1'
  loop: '{{ rsyslog_legacy_remote_listen_files }}'
  register: rsyslog_listen_legacy_comment
  when:
  - '"kernel" in ansible_facts.packages'
  - rsyslog_legacy_remote_listen_files | length > 0
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Define Rsyslog Config Lines Regex in RainerScript Syntax
  ansible.builtin.set_fact:
    rsyslog_listen_rainer_regex: ^\s*(module|input)\((load|type)="(imtcp|imudp)".*$
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Search for RainerScript Config Lines in Rsyslog Main Config File
  ansible.builtin.find:
    paths: /etc
    pattern: rsyslog.conf
    contains: '{{ rsyslog_listen_rainer_regex }}'
  register: rsyslog_rainer_remote_main_file
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Search for RainerScript Config Lines in Rsyslog Include Files
  ansible.builtin.find:
    paths: /etc/rsyslog.d/
    pattern: '*.conf'
    contains: '{{ rsyslog_listen_rainer_regex }}'
  register: rsyslog_rainer_remote_include_files
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Assemble List of Config Files With Listen Lines in RainerScript
  ansible.builtin.set_fact:
    rsyslog_rainer_remote_listen_files: '{{ rsyslog_rainer_remote_main_file.files
      | map(attribute=''path'') | list + rsyslog_rainer_remote_include_files.files
      | map(attribute=''path'') | list }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Comment Listen Config Lines Wherever Defined Using RainerScript
  ansible.builtin.replace:
    path: '{{ item }}'
    regexp: '{{ rsyslog_listen_rainer_regex }}'
    replace: '# \1'
  loop: '{{ rsyslog_rainer_remote_listen_files }}'
  register: rsyslog_listen_rainer_comment
  when:
  - '"kernel" in ansible_facts.packages'
  - rsyslog_rainer_remote_listen_files | length > 0
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten

- name: Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server
    - Restart Rsyslog if Any Line Were Commented Out
  ansible.builtin.service:
    name: rsyslog
    state: restarted
  when:
  - '"kernel" in ansible_facts.packages'
  - rsyslog_listen_legacy_comment is changed or rsyslog_listen_rainer_comment is changed
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_nolisten
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
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-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
os-srgSRG-OS-000479-GPOS-00224, SRG-OS-000480-GPOS-00227, SRG-OS-000342-GPOS-00133
anssiR71
cis5.1.1.6

Rule   Ensure rsyslog is Installed   [ref]

Rsyslog is installed by default. The rsyslog package can be installed with the following command:
 $ sudo dnf install rsyslog
Rationale:
The rsyslog package provides the rsyslog daemon, which provides system logging services.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_rsyslog_installed
References:
cis-csc1, 14, 15, 16, 3, 5, 6
cobit5APO11.04, BAI03.05, DSS05.04, DSS05.07, MEA02.01
disaCCI-000366, CCI-000154, CCI-001851
hipaa164.312(a)(2)(ii)
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
nistCM-6(a)
nist-csfPR.PT-1
os-srgSRG-OS-000479-GPOS-00224, SRG-OS-000051-GPOS-00024, SRG-OS-000480-GPOS-00227
cis5.1.1.1


[[packages]]
name = "rsyslog"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_rsyslog_installed

- name: Ensure rsyslog is installed
  package:
    name: rsyslog
    state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_rsyslog_installed

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

class install_rsyslog {
  package { 'rsyslog':
    ensure => 'installed',
  }
}

Rule   Ensure rsyslog Default File Permissions Configured   [ref]

rsyslog will create logfiles that do not already exist on the system. This settings controls what permissions will be applied to these newly created files.
Rationale:
It is important to ensure that log files have the correct permissions to ensure that sensitive data is archived and protected.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_filecreatemode
References:
cis5.1.1.4

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

readarray -t targets < <(grep -H '^\s*$FileCreateMode' /etc/rsyslog.conf /etc/rsyslog.d/*)

# if $FileCreateMode set in multiple places
if [ ${#targets[@]} -gt 1 ]; then
    # delete all and create new entry with expected value
    sed -i '/^\s*$FileCreateMode/d' /etc/rsyslog.conf /etc/rsyslog.d/*
    echo '$FileCreateMode 0640' > /etc/rsyslog.d/99-rsyslog_filecreatemode.conf
# if $FileCreateMode set in only one place
elif [ "${#targets[@]}" -eq 1 ]; then
    filename=$(echo "${targets[0]}" | cut -d':' -f1)
    value=$(echo "${targets[0]}" | cut -d' ' -f2)
    #convert to decimal and bitwise or operation
    result=$((8#$value | 416))
    # if more permissive than expected, then set it to 0640
    if [ $result -ne 416 ]; then
        # if value is wrong remove it
        sed -i '/^\s*$FileCreateMode/d' $filename
        echo '$FileCreateMode 0640' > $filename
    fi
else
    echo '$FileCreateMode 0640' > /etc/rsyslog.d/99-rsyslog_filecreatemode.conf
fi

systemctl restart rsyslog.service

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode

- name: Ensure rsyslog Default File Permissions Configured - Search for $FileCreateMode
    Parameter in rsyslog Main Config File
  ansible.builtin.find:
    paths: /etc
    pattern: rsyslog.conf
    contains: ^\s*\$FileCreateMode\s*\d+
  register: rsyslog_main_file_with_filecreatemode
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode

- name: Ensure rsyslog Default File Permissions Configured - Search for $FileCreateMode
    Parameter in rsyslog Include Files
  ansible.builtin.find:
    paths: /etc/rsyslog.d/
    pattern: '*.conf'
    contains: ^\s*\$FileCreateMode\s*\d+
  register: rsyslog_includes_with_filecreatemode
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode

- name: Ensure rsyslog Default File Permissions Configured - Assemble List of rsyslog
    Configuration Files with $FileCreateMode Parameter
  ansible.builtin.set_fact:
    rsyslog_filecreatemode_files: '{{ rsyslog_main_file_with_filecreatemode.files
      | map(attribute=''path'') | list + rsyslog_includes_with_filecreatemode.files
      | map(attribute=''path'') | list }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode

- name: Ensure rsyslog Default File Permissions Configured - Remove $FileCreateMode
    Parameter from Multiple Files to Avoid Conflicts
  ansible.builtin.lineinfile:
    path: '{{ item }}'
    regexp: \$FileCreateMode.*
    state: absent
  register: result_rsyslog_filecreatemode_removed
  loop: '{{ rsyslog_filecreatemode_files }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - rsyslog_filecreatemode_files | length > 1
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode

- name: Ensure rsyslog Default File Permissions Configured - Add $FileCreateMode Parameter
    and Expected Value
  ansible.builtin.lineinfile:
    path: /etc/rsyslog.d/99-rsyslog_filecreatemode.conf
    line: $FileCreateMode 0640
    mode: 416
    create: true
  when:
  - '"kernel" in ansible_facts.packages'
  - rsyslog_filecreatemode_files | length == 0 or result_rsyslog_filecreatemode_removed
    is not skipped
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode

- name: Ensure rsyslog Default File Permissions Configured - Ensure Correct Value
    of Existing $FileCreateMode Parameter
  ansible.builtin.lineinfile:
    path: '{{ item }}'
    regexp: ^\$FileCreateMode
    line: $FileCreateMode 0640
  loop: '{{ rsyslog_filecreatemode_files }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - rsyslog_filecreatemode_files | length == 1
  tags:
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - rsyslog_filecreatemode
Group   Network Configuration and Firewalls   Group contains 5 groups and 23 rules
[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   IPv6   Group contains 1 group and 7 rules
[ref]   The system includes support for Internet Protocol version 6. A major and often-mentioned improvement over IPv4 is its enormous increase in the number of available addresses. Another important feature is its support for automatic configuration of many network settings.
Group   Configure IPv6 Settings if Necessary   Group contains 7 rules
[ref]   A major feature of IPv6 is the extent to which systems implementing it can automatically configure their networking devices using information from the network. From a security perspective, manually configuring important configuration information is preferable to accepting it from the network in an unauthenticated fashion.

Rule   Configure Accepting Router Advertisements on All IPv6 Interfaces   [ref]

To set the runtime status of the net.ipv6.conf.all.accept_ra kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.accept_ra=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.accept_ra = 0
Rationale:
An illicit router advertisement message could result in a man-in-the-middle attack.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_ra
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.1.20
disaCCI-000366
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
cis3.3.9

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.all.accept_ra.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra

- name: Comment out any occurrences of net.ipv6.conf.all.accept_ra from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.all.accept_ra
    replace: '#net.ipv6.conf.all.accept_ra'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra
- name: XCCDF Value sysctl_net_ipv6_conf_all_accept_ra_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_all_accept_ra_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.all.accept_ra is set
  sysctl:
    name: net.ipv6.conf.all.accept_ra
    value: '{{ sysctl_net_ipv6_conf_all_accept_ra_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra

Rule   Disable Accepting ICMP Redirects for All IPv6 Interfaces   [ref]

To set the runtime status of the net.ipv6.conf.all.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.accept_redirects = 0
Rationale:
An illicit ICMP redirect message could result in a man-in-the-middle attack.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_redirects
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.1.20
disaCCI-000366
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-7(a), CM-7(b), CM-6(a), CM-6(b), CM-6.1(iv)
nist-csfPR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
anssiR13
cis3.3.2

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.all.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_redirects

- name: Comment out any occurrences of net.ipv6.conf.all.accept_redirects from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.all.accept_redirects
    replace: '#net.ipv6.conf.all.accept_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_redirects
- name: XCCDF Value sysctl_net_ipv6_conf_all_accept_redirects_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_all_accept_redirects_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.all.accept_redirects is set
  sysctl:
    name: net.ipv6.conf.all.accept_redirects
    value: '{{ sysctl_net_ipv6_conf_all_accept_redirects_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_redirects

Rule   Disable Kernel Parameter for Accepting Source-Routed Packets on all IPv6 Interfaces   [ref]

To set the runtime status of the net.ipv6.conf.all.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.accept_source_route = 0
Rationale:
Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router.

Accepting source-routed packets in the IPv6 protocol has few legitimate uses. It should be disabled unless it is absolutely required.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_source_route
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
cui3.1.20
disaCCI-000366
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
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfDE.AE-1, ID.AM-3, PR.AC-5, PR.DS-5, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR13
cis3.3.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_source_route

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.all.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_source_route

- name: Comment out any occurrences of net.ipv6.conf.all.accept_source_route from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.all.accept_source_route
    replace: '#net.ipv6.conf.all.accept_source_route'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_source_route
- name: XCCDF Value sysctl_net_ipv6_conf_all_accept_source_route_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_all_accept_source_route_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.all.accept_source_route is set
  sysctl:
    name: net.ipv6.conf.all.accept_source_route
    value: '{{ sysctl_net_ipv6_conf_all_accept_source_route_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_source_route

Rule   Disable Kernel Parameter for IPv6 Forwarding   [ref]

To set the runtime status of the net.ipv6.conf.all.forwarding kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.forwarding=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.forwarding = 0
Rationale:
IP forwarding permits the kernel to forward packets from one network interface to another. The ability to forward packets between two networks is only appropriate for systems acting as routers.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_forwarding
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 7, 8, 9
cobit5APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS05.02, DSS05.05, DSS05.07, DSS06.06
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, SR 7.6
iso27001-2013A.12.1.2, A.12.1.3, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), CM-6(b), CM-6.1(iv)
nist-csfDE.CM-1, PR.DS-4, PR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
cis3.2.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_forwarding

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.all.forwarding.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_forwarding

- name: Comment out any occurrences of net.ipv6.conf.all.forwarding from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.all.forwarding
    replace: '#net.ipv6.conf.all.forwarding'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_forwarding
- name: XCCDF Value sysctl_net_ipv6_conf_all_forwarding_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_all_forwarding_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.all.forwarding is set
  sysctl:
    name: net.ipv6.conf.all.forwarding
    value: '{{ sysctl_net_ipv6_conf_all_forwarding_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_forwarding

Rule   Disable Accepting Router Advertisements on all IPv6 Interfaces by Default   [ref]

To set the runtime status of the net.ipv6.conf.default.accept_ra kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.default.accept_ra=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.default.accept_ra = 0
Rationale:
An illicit router advertisement message could result in a man-in-the-middle attack.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_ra
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.1.20
disaCCI-000366
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
cis3.3.9

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_ra

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.default.accept_ra.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_ra

- name: Comment out any occurrences of net.ipv6.conf.default.accept_ra from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.default.accept_ra
    replace: '#net.ipv6.conf.default.accept_ra'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_ra
- name: XCCDF Value sysctl_net_ipv6_conf_default_accept_ra_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_default_accept_ra_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.default.accept_ra is set
  sysctl:
    name: net.ipv6.conf.default.accept_ra
    value: '{{ sysctl_net_ipv6_conf_default_accept_ra_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_ra

Rule   Disable Kernel Parameter for Accepting ICMP Redirects by Default on IPv6 Interfaces   [ref]

To set the runtime status of the net.ipv6.conf.default.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.default.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.default.accept_redirects = 0
Rationale:
An illicit ICMP redirect message could result in a man-in-the-middle attack.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_redirects
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.1.20
disaCCI-000366
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
anssiR13
cis3.3.2

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.default.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_redirects

- name: Comment out any occurrences of net.ipv6.conf.default.accept_redirects from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.default.accept_redirects
    replace: '#net.ipv6.conf.default.accept_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_redirects
- name: XCCDF Value sysctl_net_ipv6_conf_default_accept_redirects_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_default_accept_redirects_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.default.accept_redirects is set
  sysctl:
    name: net.ipv6.conf.default.accept_redirects
    value: '{{ sysctl_net_ipv6_conf_default_accept_redirects_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_redirects

Rule   Disable Kernel Parameter for Accepting Source-Routed Packets on IPv6 Interfaces by Default   [ref]

To set the runtime status of the net.ipv6.conf.default.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.default.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.default.accept_source_route = 0
Rationale:
Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router. Accepting source-routed packets in the IPv6 protocol has few legitimate uses. It should be disabled unless it is absolutely required.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_source_route
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
cui3.1.20
disaCCI-000366
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
nistCM-7(a), CM-7(b), CM-6(a), CM-6(b), CM-6.1(iv)
nist-csfDE.AE-1, ID.AM-3, PR.AC-5, PR.DS-5, PR.PT-4
pcidssReq-1.4.3
os-srgSRG-OS-000480-GPOS-00227
anssiR13
cis3.3.1
pcidss41.4.2, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_source_route

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.default.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_source_route

- name: Comment out any occurrences of net.ipv6.conf.default.accept_source_route from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.default.accept_source_route
    replace: '#net.ipv6.conf.default.accept_source_route'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_source_route
- name: XCCDF Value sysctl_net_ipv6_conf_default_accept_source_route_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_default_accept_source_route_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.default.accept_source_route is set
  sysctl:
    name: net.ipv6.conf.default.accept_source_route
    value: '{{ sysctl_net_ipv6_conf_default_accept_source_route_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(b)
  - NIST-800-53-CM-6.1(iv)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_default_accept_source_route
Group   Kernel Parameters Which Affect Networking   Group contains 2 groups and 16 rules
[ref]   The sysctl utility is used to set parameters which affect the operation of the Linux kernel. Kernel parameters which affect networking and have security implications are described here.
Group   Network Related Kernel Runtime Parameters for Hosts and Routers   Group contains 13 rules
[ref]   Certain kernel parameters should be set for systems which are acting as either hosts or routers to improve the system's ability defend against certain types of IPv4 protocol attacks.

Rule   Disable Accepting ICMP Redirects for All IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.all.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.accept_redirects = 0
Rationale:
ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless absolutely required."
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_accept_redirects
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 7, 8, 9
cjis5.10.1.1
cobit5APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS05.02, DSS05.05, DSS05.07, DSS06.06
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, SR 7.6
iso27001-2013A.12.1.2, A.12.1.3, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), SC-7(a)
nist-csfDE.CM-1, PR.DS-4, PR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.2

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.all.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_redirects

- name: Comment out any occurrences of net.ipv4.conf.all.accept_redirects from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.all.accept_redirects
    replace: '#net.ipv4.conf.all.accept_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_redirects
- name: XCCDF Value sysctl_net_ipv4_conf_all_accept_redirects_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_all_accept_redirects_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.all.accept_redirects is set
  sysctl:
    name: net.ipv4.conf.all.accept_redirects
    value: '{{ sysctl_net_ipv4_conf_all_accept_redirects_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_redirects

Rule   Disable Kernel Parameter for Accepting Source-Routed Packets on all IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.all.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.accept_source_route = 0
Rationale:
Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv4 forwarding is enabled and the system is functioning as a router.

Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_accept_source_route
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-000366
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5, CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_source_route

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.all.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_source_route

- name: Comment out any occurrences of net.ipv4.conf.all.accept_source_route from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.all.accept_source_route
    replace: '#net.ipv4.conf.all.accept_source_route'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_source_route
- name: XCCDF Value sysctl_net_ipv4_conf_all_accept_source_route_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_all_accept_source_route_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.all.accept_source_route is set
  sysctl:
    name: net.ipv4.conf.all.accept_source_route
    value: '{{ sysctl_net_ipv4_conf_all_accept_source_route_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_accept_source_route

Rule   Enable Kernel Parameter to Log Martian Packets on all IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.all.log_martians kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.log_martians=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.log_martians = 1
Rationale:
The presence of "martian" packets (which have impossible addresses) as well as spoofed packets, source-routed packets, and redirects could be a sign of nefarious network activity. Logging these packets enables this activity to be detected.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_log_martians
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 7, 8, 9
cobit5APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.04, DSS03.05, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.06
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.1.3, 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.17.2.1, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), SC-5(3)(a)
nist-csfDE.CM-1, PR.AC-3, PR.DS-4, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
cis3.3.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_all_log_martians
  - unknown_severity

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.all.log_martians.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_all_log_martians
  - unknown_severity

- name: Comment out any occurrences of net.ipv4.conf.all.log_martians from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.all.log_martians
    replace: '#net.ipv4.conf.all.log_martians'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_all_log_martians
  - unknown_severity
- name: XCCDF Value sysctl_net_ipv4_conf_all_log_martians_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_all_log_martians_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.all.log_martians is set
  sysctl:
    name: net.ipv4.conf.all.log_martians
    value: '{{ sysctl_net_ipv4_conf_all_log_martians_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_all_log_martians
  - unknown_severity

Rule   Enable Kernel Parameter to Use Reverse Path Filtering on all IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.all.rp_filter kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.rp_filter=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.rp_filter = 1
Rationale:
Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems which are routers for complicated networks, but is helpful for end hosts and routers serving small networks.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_rp_filter
References:
cis-csc1, 12, 13, 14, 15, 16, 18, 2, 4, 6, 7, 8, 9
cobit5APO01.06, APO13.01, BAI04.04, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.07, DSS06.02
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, 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.12.1.3, 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.17.2.1, 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-7(a), CM-7(b), CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.PT-4
pcidssReq-1.4.3
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.7
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_rp_filter

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.all.rp_filter.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_rp_filter

- name: Comment out any occurrences of net.ipv4.conf.all.rp_filter from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.all.rp_filter
    replace: '#net.ipv4.conf.all.rp_filter'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_rp_filter
- name: XCCDF Value sysctl_net_ipv4_conf_all_rp_filter_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_all_rp_filter_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.all.rp_filter is set
  sysctl:
    name: net.ipv4.conf.all.rp_filter
    value: '{{ sysctl_net_ipv4_conf_all_rp_filter_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_rp_filter

Rule   Disable Kernel Parameter for Accepting Secure ICMP Redirects on all IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.all.secure_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.secure_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.secure_redirects = 0
Rationale:
Accepting "secure" ICMP redirects (from those gateways listed as default gateways) has few legitimate uses. It should be disabled unless it is absolutely required.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_secure_redirects
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-001503, CCI-001551
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-7(a), CM-7(b), CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-1.4.3
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.3
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_secure_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.all.secure_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_secure_redirects

- name: Comment out any occurrences of net.ipv4.conf.all.secure_redirects from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.all.secure_redirects
    replace: '#net.ipv4.conf.all.secure_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_secure_redirects
- name: XCCDF Value sysctl_net_ipv4_conf_all_secure_redirects_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_all_secure_redirects_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.all.secure_redirects is set
  sysctl:
    name: net.ipv4.conf.all.secure_redirects
    value: '{{ sysctl_net_ipv4_conf_all_secure_redirects_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_secure_redirects

Rule   Disable Kernel Parameter for Accepting ICMP Redirects by Default on IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.default.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.accept_redirects = 0
Rationale:
ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless absolutely required.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_accept_redirects
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cjis5.10.1.1
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-000366
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-7(a), CM-7(b), CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-1.4.3
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.2
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.default.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_redirects

- name: Comment out any occurrences of net.ipv4.conf.default.accept_redirects from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.default.accept_redirects
    replace: '#net.ipv4.conf.default.accept_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_redirects
- name: XCCDF Value sysctl_net_ipv4_conf_default_accept_redirects_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_default_accept_redirects_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.default.accept_redirects is set
  sysctl:
    name: net.ipv4.conf.default.accept_redirects
    value: '{{ sysctl_net_ipv4_conf_default_accept_redirects_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_redirects

Rule   Disable Kernel Parameter for Accepting Source-Routed Packets on IPv4 Interfaces by Default   [ref]

To set the runtime status of the net.ipv4.conf.default.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.accept_source_route = 0
Rationale:
Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures.
Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required, such as when IPv4 forwarding is enabled and the system is legitimately functioning as a router.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_accept_source_route
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cjis5.10.1.1
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-000366
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5, SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_source_route

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.default.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_source_route

- name: Comment out any occurrences of net.ipv4.conf.default.accept_source_route from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.default.accept_source_route
    replace: '#net.ipv4.conf.default.accept_source_route'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_source_route
- name: XCCDF Value sysctl_net_ipv4_conf_default_accept_source_route_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_default_accept_source_route_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.default.accept_source_route is set
  sysctl:
    name: net.ipv4.conf.default.accept_source_route
    value: '{{ sysctl_net_ipv4_conf_default_accept_source_route_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_accept_source_route

Rule   Enable Kernel Paremeter to Log Martian Packets on all IPv4 Interfaces by Default   [ref]

To set the runtime status of the net.ipv4.conf.default.log_martians kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.log_martians=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.log_martians = 1
Rationale:
The presence of "martian" packets (which have impossible addresses) as well as spoofed packets, source-routed packets, and redirects could be a sign of nefarious network activity. Logging these packets enables this activity to be detected.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_log_martians
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 7, 8, 9
cobit5APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.04, DSS03.05, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.06
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.1.3, 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.17.2.1, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), SC-5(3)(a)
nist-csfDE.CM-1, PR.AC-3, PR.DS-4, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
cis3.3.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_default_log_martians
  - unknown_severity

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.default.log_martians.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_default_log_martians
  - unknown_severity

- name: Comment out any occurrences of net.ipv4.conf.default.log_martians from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.default.log_martians
    replace: '#net.ipv4.conf.default.log_martians'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_default_log_martians
  - unknown_severity
- name: XCCDF Value sysctl_net_ipv4_conf_default_log_martians_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_default_log_martians_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.default.log_martians is set
  sysctl:
    name: net.ipv4.conf.default.log_martians
    value: '{{ sysctl_net_ipv4_conf_default_log_martians_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(3)(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_conf_default_log_martians
  - unknown_severity

Rule   Enable Kernel Parameter to Use Reverse Path Filtering on all IPv4 Interfaces by Default   [ref]

To set the runtime status of the net.ipv4.conf.default.rp_filter kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.rp_filter=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.rp_filter = 1
Rationale:
Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems which are routers for complicated networks, but is helpful for end hosts and routers serving small networks.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_rp_filter
References:
cis-csc1, 12, 13, 14, 15, 16, 18, 2, 4, 6, 7, 8, 9
cobit5APO01.06, APO13.01, BAI04.04, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.07, DSS06.02
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, 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.12.1.3, 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.17.2.1, 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-7(a), CM-7(b), CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.7

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_rp_filter

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.default.rp_filter.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_rp_filter

- name: Comment out any occurrences of net.ipv4.conf.default.rp_filter from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.default.rp_filter
    replace: '#net.ipv4.conf.default.rp_filter'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_rp_filter
- name: XCCDF Value sysctl_net_ipv4_conf_default_rp_filter_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_default_rp_filter_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.default.rp_filter is set
  sysctl:
    name: net.ipv4.conf.default.rp_filter
    value: '{{ sysctl_net_ipv4_conf_default_rp_filter_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_rp_filter

Rule   Configure Kernel Parameter for Accepting Secure Redirects By Default   [ref]

To set the runtime status of the net.ipv4.conf.default.secure_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.secure_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.secure_redirects = 0
Rationale:
Accepting "secure" ICMP redirects (from those gateways listed as default gateways) has few legitimate uses. It should be disabled unless it is absolutely required.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_secure_redirects
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-001551
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5, SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.3

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_secure_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.default.secure_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_secure_redirects

- name: Comment out any occurrences of net.ipv4.conf.default.secure_redirects from
    config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.default.secure_redirects
    replace: '#net.ipv4.conf.default.secure_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_secure_redirects
- name: XCCDF Value sysctl_net_ipv4_conf_default_secure_redirects_value # promote to variable
  set_fact:
    sysctl_net_ipv4_conf_default_secure_redirects_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv4.conf.default.secure_redirects is set
  sysctl:
    name: net.ipv4.conf.default.secure_redirects
    value: '{{ sysctl_net_ipv4_conf_default_secure_redirects_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_secure_redirects

Rule   Enable Kernel Parameter to Ignore ICMP Broadcast Echo Requests on IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.icmp_echo_ignore_broadcasts kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.icmp_echo_ignore_broadcasts = 1
Rationale:
Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks.
Ignoring ICMP echo requests (pings) sent to broadcast or multicast addresses makes the system slightly more difficult to enumerate on the network.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_icmp_echo_ignore_broadcasts
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cjis5.10.1.1
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-000366
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-1.4.3
os-srgSRG-OS-000480-GPOS-00227
cis3.3.5
pcidss41.4.2, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_icmp_echo_ignore_broadcasts

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.icmp_echo_ignore_broadcasts.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_icmp_echo_ignore_broadcasts

- name: Comment out any occurrences of net.ipv4.icmp_echo_ignore_broadcasts from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.icmp_echo_ignore_broadcasts
    replace: '#net.ipv4.icmp_echo_ignore_broadcasts'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_icmp_echo_ignore_broadcasts
- name: XCCDF Value sysctl_net_ipv4_icmp_echo_ignore_broadcasts_value # promote to variable
  set_fact:
    sysctl_net_ipv4_icmp_echo_ignore_broadcasts_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.icmp_echo_ignore_broadcasts is set
  sysctl:
    name: net.ipv4.icmp_echo_ignore_broadcasts
    value: '{{ sysctl_net_ipv4_icmp_echo_ignore_broadcasts_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_icmp_echo_ignore_broadcasts

Rule   Enable Kernel Parameter to Ignore Bogus ICMP Error Responses on IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.icmp_ignore_bogus_error_responses kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.icmp_ignore_bogus_error_responses=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.icmp_ignore_bogus_error_responses = 1
Rationale:
Ignoring bogus ICMP error responses reduces log size, although some activity would not be logged.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_icmp_ignore_bogus_error_responses
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 7, 8, 9
cobit5APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS05.02, DSS05.05, DSS05.07, DSS06.06
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, SR 7.6
iso27001-2013A.12.1.2, A.12.1.3, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, A.9.1.2
nerc-cipCIP-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5
nist-csfDE.CM-1, PR.DS-4, PR.IP-1, PR.PT-3
pcidssReq-1.4.3
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.3.6
pcidss41.4.2, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_icmp_ignore_bogus_error_responses
  - unknown_severity

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.icmp_ignore_bogus_error_responses.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_icmp_ignore_bogus_error_responses
  - unknown_severity

- name: Comment out any occurrences of net.ipv4.icmp_ignore_bogus_error_responses
    from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.icmp_ignore_bogus_error_responses
    replace: '#net.ipv4.icmp_ignore_bogus_error_responses'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_icmp_ignore_bogus_error_responses
  - unknown_severity
- name: XCCDF Value sysctl_net_ipv4_icmp_ignore_bogus_error_responses_value # promote to variable
  set_fact:
    sysctl_net_ipv4_icmp_ignore_bogus_error_responses_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.icmp_ignore_bogus_error_responses is set
  sysctl:
    name: net.ipv4.icmp_ignore_bogus_error_responses
    value: '{{ sysctl_net_ipv4_icmp_ignore_bogus_error_responses_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - PCI-DSS-Req-1.4.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.2
  - disable_strategy
  - low_complexity
  - medium_disruption
  - reboot_required
  - sysctl_net_ipv4_icmp_ignore_bogus_error_responses
  - unknown_severity

Rule   Enable Kernel Parameter to Use TCP Syncookies on Network Interfaces   [ref]

To set the runtime status of the net.ipv4.tcp_syncookies kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.tcp_syncookies=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.tcp_syncookies = 1
Rationale:
A TCP SYN flood attack can cause a denial of service by filling a system's TCP connection table with connections in the SYN_RCVD state. Syncookies can be used to track a connection when a subsequent ACK is received, verifying the initiator is attempting a valid connection and is not a flood source. This feature is activated when a flood condition is detected, and enables the system to continue servicing valid connection requests.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_tcp_syncookies
References:
cis-csc1, 12, 13, 14, 15, 16, 18, 2, 4, 6, 7, 8, 9
cjis5.10.1.1
cobit5APO01.06, APO13.01, BAI04.04, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.07, DSS06.02
cui3.1.20
disaCCI-001095, CCI-000366, CCI-002385
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 6.2, SR 7.1, SR 7.2, 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.12.1.3, 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.17.2.1, 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-7(a), CM-7(b), SC-5(1), SC-5(2), SC-5(3)(a), CM-6(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.PT-4
pcidssReq-1.4.1
os-srgSRG-OS-000480-GPOS-00227, SRG-OS-000420-GPOS-00186, SRG-OS-000142-GPOS-00071
anssiR12
cis3.3.8
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(1)
  - NIST-800-53-SC-5(2)
  - NIST-800-53-SC-5(3)(a)
  - PCI-DSS-Req-1.4.1
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_tcp_syncookies

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.tcp_syncookies.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(1)
  - NIST-800-53-SC-5(2)
  - NIST-800-53-SC-5(3)(a)
  - PCI-DSS-Req-1.4.1
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_tcp_syncookies

- name: Comment out any occurrences of net.ipv4.tcp_syncookies from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.tcp_syncookies
    replace: '#net.ipv4.tcp_syncookies'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(1)
  - NIST-800-53-SC-5(2)
  - NIST-800-53-SC-5(3)(a)
  - PCI-DSS-Req-1.4.1
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_tcp_syncookies
- name: XCCDF Value sysctl_net_ipv4_tcp_syncookies_value # promote to variable
  set_fact:
    sysctl_net_ipv4_tcp_syncookies_value: !!str 1
  tags:
    - always

- name: Ensure sysctl net.ipv4.tcp_syncookies is set
  sysctl:
    name: net.ipv4.tcp_syncookies
    value: '{{ sysctl_net_ipv4_tcp_syncookies_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5(1)
  - NIST-800-53-SC-5(2)
  - NIST-800-53-SC-5(3)(a)
  - PCI-DSS-Req-1.4.1
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_tcp_syncookies
Group   Network Parameters for Hosts Only   Group contains 3 rules
[ref]   If the system is not going to be used as a router, then setting certain kernel parameters ensure that the host will not perform routing of network traffic.

Rule   Disable Kernel Parameter for Sending ICMP Redirects on all IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.conf.all.send_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.send_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.send_redirects = 0
Rationale:
ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.
The ability to send ICMP redirects is only appropriate for systems acting as routers.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_send_redirects
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cjis5.10.1.1
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-000366
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5, CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.2.2
pcidss41.4.5, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_send_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.all.send_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_send_redirects

- name: Comment out any occurrences of net.ipv4.conf.all.send_redirects from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.all.send_redirects
    replace: '#net.ipv4.conf.all.send_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_send_redirects

- name: Ensure sysctl net.ipv4.conf.all.send_redirects is set to 0
  sysctl:
    name: net.ipv4.conf.all.send_redirects
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_all_send_redirects

Rule   Disable Kernel Parameter for Sending ICMP Redirects on all IPv4 Interfaces by Default   [ref]

To set the runtime status of the net.ipv4.conf.default.send_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.send_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.send_redirects = 0
Rationale:
ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.
The ability to send ICMP redirects is only appropriate for systems acting as routers.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_send_redirects
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 2, 3, 4, 6, 7, 8, 9
cjis5.10.1.1
cobit5APO01.06, APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS01.05, DSS03.01, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.06
cui3.1.20
disaCCI-000366
isa-62443-20094.2.3.4, 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, 4.3.4.3.2, 4.3.4.3.3, 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 2.2, 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 6.2, SR 7.1, SR 7.2, 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.12.1.3, A.12.5.1, A.12.6.2, 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.14.2.2, A.14.2.3, A.14.2.4, A.17.2.1, 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-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5, CM-6(a), SC-7(a)
nist-csfDE.AE-1, DE.CM-1, ID.AM-3, PR.AC-5, PR.DS-4, PR.DS-5, PR.IP-1, PR.PT-3, PR.PT-4
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.2.2
pcidss41.4.5, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_send_redirects

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.conf.default.send_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_send_redirects

- name: Comment out any occurrences of net.ipv4.conf.default.send_redirects from config
    files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.conf.default.send_redirects
    replace: '#net.ipv4.conf.default.send_redirects'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_send_redirects

- name: Ensure sysctl net.ipv4.conf.default.send_redirects is set to 0
  sysctl:
    name: net.ipv4.conf.default.send_redirects
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.10.1.1
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.5
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_conf_default_send_redirects

Rule   Disable Kernel Parameter for IP Forwarding on IPv4 Interfaces   [ref]

To set the runtime status of the net.ipv4.ip_forward kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.ip_forward=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.ip_forward = 0
Warning:  Certain technologies such as virtual machines, containers, etc. rely on IPv4 forwarding to enable and use networking. Disabling IPv4 forwarding would cause those technologies to stop working. Therefore, this rule should not be used in profiles or benchmarks that target usage of IPv4 forwarding.
Rationale:
Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this capability is used when not required, system network information may be unnecessarily transmitted across the network.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_ip_forward
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 2, 3, 7, 8, 9
cobit5APO13.01, BAI04.04, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS05.02, DSS05.05, DSS05.07, DSS06.06
cui3.1.20
disaCCI-000366
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 6.2, SR 7.1, SR 7.2, SR 7.6
iso27001-2013A.12.1.2, A.12.1.3, 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.17.2.1, A.9.1.2
nerc-cipCIP-007-3 R4, CIP-007-3 R4.1, CIP-007-3 R4.2, CIP-007-3 R5.1
nistCM-7(a), CM-7(b), SC-5, CM-6(a), SC-7(a)
nist-csfDE.CM-1, PR.DS-4, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-1.3.1, Req-1.3.2
os-srgSRG-OS-000480-GPOS-00227
anssiR12
cis3.2.1
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.3.1
  - PCI-DSS-Req-1.3.2
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_ip_forward

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*net.ipv4.ip_forward.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.3.1
  - PCI-DSS-Req-1.3.2
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_ip_forward

- name: Comment out any occurrences of net.ipv4.ip_forward from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv4.ip_forward
    replace: '#net.ipv4.ip_forward'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.3.1
  - PCI-DSS-Req-1.3.2
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_ip_forward

- name: Ensure sysctl net.ipv4.ip_forward is set to 0
  sysctl:
    name: net.ipv4.ip_forward
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-5
  - NIST-800-53-SC-7(a)
  - PCI-DSS-Req-1.3.1
  - PCI-DSS-Req-1.3.2
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.3
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv4_ip_forward
Group   File Permissions and Masks   Group contains 7 groups and 57 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 Amazon Linux 2023 installations:
$ mount -t xfs | awk '{print $3}'
For any systems that use a different local filesystem type, modify this command as appropriate.
Group   Verify Permissions on Important Files and Directories   Group contains 1 group and 28 rules
[ref]   Permissions for many files on a system must be set restrictively to ensure sensitive information is properly protected. This section discusses important permission restrictions which can be verified to ensure that no harmful discrepancies have arisen.
Group   Verify Permissions on Files with Local Account Information and Credentials   Group contains 24 rules

Rule   Verify Group Who Owns Backup group File   [ref]

To properly set the group owner of /etc/group-, run the command:
$ sudo chgrp root /etc/group-
Rationale:
The /etc/group- file is a backup file of /etc/group, and as such, it contains information regarding groups that are configured on the system. Protection of this file is important for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_backup_etc_group
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7
os-srgSRG-OS-000480-GPOS-00227
cis6.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/group-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/group-
  stat:
    path: /etc/group-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_backup_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/group-
  file:
    path: /etc/group-
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_backup_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns Backup gshadow File   [ref]

To properly set the group owner of /etc/gshadow-, run the command:
$ sudo chgrp root /etc/gshadow-
Rationale:
The /etc/gshadow- file is a backup of /etc/gshadow, and as such, it contains group password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_backup_etc_gshadow
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7
os-srgSRG-OS-000480-GPOS-00227
cis6.1.9

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/gshadow-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/gshadow-
  stat:
    path: /etc/gshadow-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - configure_strategy
  - file_groupowner_backup_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/gshadow-
  file:
    path: /etc/gshadow-
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - configure_strategy
  - file_groupowner_backup_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns Backup passwd File   [ref]

To properly set the group owner of /etc/passwd-, run the command:
$ sudo chgrp root /etc/passwd-
Rationale:
The /etc/passwd- file is a backup file of /etc/passwd, and as such, it contains information about the users that are configured on the system. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_backup_etc_passwd
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7
os-srgSRG-OS-000480-GPOS-00227
cis6.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/passwd-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/passwd-
  stat:
    path: /etc/passwd-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_backup_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/passwd-
  file:
    path: /etc/passwd-
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_backup_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns Backup shadow File   [ref]

To properly set the group owner of /etc/shadow-, run the command:
$ sudo chgrp root /etc/shadow-
Rationale:
The /etc/shadow- file is a backup file of /etc/shadow, and as such, it contains the list of local system accounts and password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_backup_etc_shadow
References:
disaCCI-000366
pcidssReq-8.7
os-srgSRG-OS-000480-GPOS-00227
cis6.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/shadow-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shadow-
  stat:
    path: /etc/shadow-
  register: file_exists
  tags:
  - PCI-DSS-Req-8.7
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_backup_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/shadow-
  file:
    path: /etc/shadow-
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSS-Req-8.7
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_backup_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns group File   [ref]

To properly set the group owner of /etc/group, run the command:
$ sudo chgrp root /etc/group
Rationale:
The /etc/group file contains information regarding groups that are configured on the system. Protection of this file is important for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_group
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/group

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/group
  stat:
    path: /etc/group
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/group
  file:
    path: /etc/group
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns gshadow File   [ref]

To properly set the group owner of /etc/gshadow, run the command:
$ sudo chgrp root /etc/gshadow
Rationale:
The /etc/gshadow file contains group password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_gshadow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.8

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/gshadow

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/gshadow
  stat:
    path: /etc/gshadow
  register: file_exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_groupowner_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/gshadow
  file:
    path: /etc/gshadow
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_groupowner_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns passwd File   [ref]

To properly set the group owner of /etc/passwd, run the command:
$ sudo chgrp root /etc/passwd
Rationale:
The /etc/passwd file contains information about the users that are configured on the system. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_passwd
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.1, 6.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/passwd
  stat:
    path: /etc/passwd
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/passwd
  file:
    path: /etc/passwd
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns shadow File   [ref]

To properly set the group owner of /etc/shadow, run the command:
$ sudo chgrp root /etc/shadow
Rationale:
The /etc/shadow file stores password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_shadow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/shadow

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shadow
  stat:
    path: /etc/shadow
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/shadow
  file:
    path: /etc/shadow
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns Backup group File   [ref]

To properly set the owner of /etc/group-, run the command:
$ sudo chown root /etc/group- 
Rationale:
The /etc/group- file is a backup file of /etc/group, and as such, it contains information regarding groups that are configured on the system. Protection of this file is important for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_backup_etc_group
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
cis6.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/group-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/group-
  stat:
    path: /etc/group-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_backup_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/group-
  file:
    path: /etc/group-
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_backup_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns Backup gshadow File   [ref]

To properly set the owner of /etc/gshadow-, run the command:
$ sudo chown root /etc/gshadow- 
Rationale:
The /etc/gshadow- file is a backup of /etc/gshadow, and as such, it contains group password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_backup_etc_gshadow
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7
os-srgSRG-OS-000480-GPOS-00227
cis6.1.9

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/gshadow-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/gshadow-
  stat:
    path: /etc/gshadow-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - configure_strategy
  - file_owner_backup_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/gshadow-
  file:
    path: /etc/gshadow-
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7
  - configure_strategy
  - file_owner_backup_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns Backup passwd File   [ref]

To properly set the owner of /etc/passwd-, run the command:
$ sudo chown root /etc/passwd- 
Rationale:
The /etc/passwd- file is a backup file of /etc/passwd, and as such, it contains information about the users that are configured on the system. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_backup_etc_passwd
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
cis6.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/passwd-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/passwd-
  stat:
    path: /etc/passwd-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_backup_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/passwd-
  file:
    path: /etc/passwd-
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_backup_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns Backup shadow File   [ref]

To properly set the owner of /etc/shadow-, run the command:
$ sudo chown root /etc/shadow- 
Rationale:
The /etc/shadow- file is a backup file of /etc/shadow, and as such, it contains the list of local system accounts and password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_backup_etc_shadow
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
cis6.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/shadow-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shadow-
  stat:
    path: /etc/shadow-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_backup_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/shadow-
  file:
    path: /etc/shadow-
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_backup_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns group File   [ref]

To properly set the owner of /etc/group, run the command:
$ sudo chown root /etc/group 
Rationale:
The /etc/group file contains information regarding groups that are configured on the system. Protection of this file is important for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_group
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/group

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/group
  stat:
    path: /etc/group
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/group
  file:
    path: /etc/group
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns gshadow File   [ref]

To properly set the owner of /etc/gshadow, run the command:
$ sudo chown root /etc/gshadow 
Rationale:
The /etc/gshadow file contains group password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_gshadow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.8

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/gshadow

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/gshadow
  stat:
    path: /etc/gshadow
  register: file_exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_owner_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/gshadow
  file:
    path: /etc/gshadow
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_owner_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns passwd File   [ref]

To properly set the owner of /etc/passwd, run the command:
$ sudo chown root /etc/passwd 
Rationale:
The /etc/passwd file contains information about the users that are configured on the system. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_passwd
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.1, 6.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/passwd
  stat:
    path: /etc/passwd
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/passwd
  file:
    path: /etc/passwd
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns shadow File   [ref]

To properly set the owner of /etc/shadow, run the command:
$ sudo chown root /etc/shadow 
Rationale:
The /etc/shadow file contains the list of local system accounts and stores password hashes. Protection of this file is critical for system security. Failure to give ownership of this file to root provides the designated owner with access to sensitive information which could weaken the system security posture.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_shadow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/shadow

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shadow
  stat:
    path: /etc/shadow
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/shadow
  file:
    path: /etc/shadow
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on Backup group File   [ref]

To properly set the permissions of /etc/group-, run the command:
$ sudo chmod 0644 /etc/group-
Rationale:
The /etc/group- file is a backup file of /etc/group, and as such, it contains information regarding groups that are configured on the system. Protection of this file is important for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_backup_etc_group
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
cis6.1.5
pcidss42.2.6, 2.2

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




chmod u-xs,g-xws,o-xwt /etc/group-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/group-
  stat:
    path: /etc/group-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_backup_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/group-
  file:
    path: /etc/group-
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_backup_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on Backup gshadow File   [ref]

To properly set the permissions of /etc/gshadow-, run the command:
$ sudo chmod 0000 /etc/gshadow-
Rationale:
The /etc/gshadow- file is a backup of /etc/gshadow, and as such, it contains group password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_backup_etc_gshadow
References:
disaCCI-000366
nistAC-6 (1)
os-srgSRG-OS-000480-GPOS-00227
cis6.1.9

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




chmod u-xwrs,g-xwrs,o-xwrt /etc/gshadow-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/gshadow-
  stat:
    path: /etc/gshadow-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - configure_strategy
  - file_permissions_backup_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xwrs,g-xwrs,o-xwrt on /etc/gshadow-
  file:
    path: /etc/gshadow-
    mode: u-xwrs,g-xwrs,o-xwrt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - configure_strategy
  - file_permissions_backup_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on Backup passwd File   [ref]

To properly set the permissions of /etc/passwd-, run the command:
$ sudo chmod 0644 /etc/passwd-
Rationale:
The /etc/passwd- file is a backup file of /etc/passwd, and as such, it contains information about the users that are configured on the system. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_backup_etc_passwd
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
cis6.1.3
pcidss42.2.6, 2.2

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




chmod u-xs,g-xws,o-xwt /etc/passwd-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/passwd-
  stat:
    path: /etc/passwd-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_backup_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/passwd-
  file:
    path: /etc/passwd-
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_backup_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on Backup shadow File   [ref]

To properly set the permissions of /etc/shadow-, run the command:
$ sudo chmod 0000 /etc/shadow-
Rationale:
The /etc/shadow- file is a backup file of /etc/shadow, and as such, it contains the list of local system accounts and password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_backup_etc_shadow
References:
disaCCI-000366
nistAC-6 (1)
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
cis6.1.7
pcidss42.2.6, 2.2

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




chmod u-xwrs,g-xwrs,o-xwrt /etc/shadow-

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shadow-
  stat:
    path: /etc/shadow-
  register: file_exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_backup_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xwrs,g-xwrs,o-xwrt on /etc/shadow-
  file:
    path: /etc/shadow-
    mode: u-xwrs,g-xwrs,o-xwrt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6 (1)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_backup_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on group File   [ref]

To properly set the permissions of /etc/group, run the command:
$ sudo chmod 0644 /etc/group
Rationale:
The /etc/group file contains information regarding groups that are configured on the system. Protection of this file is important for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_group
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.4
pcidss42.2.6, 2.2

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




chmod u-xs,g-xws,o-xwt /etc/group

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/group
  stat:
    path: /etc/group
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/group
  file:
    path: /etc/group
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_etc_group
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on gshadow File   [ref]

To properly set the permissions of /etc/gshadow, run the command:
$ sudo chmod 0000 /etc/gshadow
Rationale:
The /etc/gshadow file contains group password hashes. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_gshadow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.8

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




chmod u-xwrs,g-xwrs,o-xwrt /etc/gshadow

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/gshadow
  stat:
    path: /etc/gshadow
  register: file_exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xwrs,g-xwrs,o-xwrt on /etc/gshadow
  file:
    path: /etc/gshadow
    mode: u-xwrs,g-xwrs,o-xwrt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_etc_gshadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on passwd File   [ref]

To properly set the permissions of /etc/passwd, run the command:
$ sudo chmod 0644 /etc/passwd
Rationale:
If the /etc/passwd file is writable by a group-owner or the world the risk of its compromise is increased. The file contains the list of accounts on the system and associated information, and protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_passwd
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.1, 6.1.2
pcidss42.2.6, 2.2

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




chmod u-xs,g-xws,o-xwt /etc/passwd

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/passwd
  stat:
    path: /etc/passwd
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/passwd
  file:
    path: /etc/passwd
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_etc_passwd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on shadow File   [ref]

To properly set the permissions of /etc/shadow, run the command:
$ sudo chmod 0000 /etc/shadow
Rationale:
The /etc/shadow file contains the list of local system accounts and stores password hashes. Protection of this file is critical for system security. Failure to give ownership of this file to root provides the designated owner with access to sensitive information which could weaken the system security posture.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_shadow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cjis5.5.2.2
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
pcidssReq-8.7.c
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis6.1.6
pcidss42.2.6, 2.2

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




chmod u-xwrs,g-xwrs,o-xwrt /etc/shadow

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shadow
  stat:
    path: /etc/shadow
  register: file_exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xwrs,g-xwrs,o-xwrt on /etc/shadow
  file:
    path: /etc/shadow
    mode: u-xwrs,g-xwrs,o-xwrt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.7.c
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_etc_shadow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify that All World-Writable Directories Have Sticky Bits Set   [ref]

When the so-called 'sticky bit' is set on a directory, only the owner of a given file may remove that file from the directory. Without the sticky bit, any user with write access to a directory may remove any file in the directory. Setting the sticky bit prevents users from removing each other's files. In cases where there is no reason for a directory to be world-writable, a better solution is to remove that permission rather than to set the sticky bit. However, if a directory is used by a particular application, consult that application's documentation instead of blindly changing modes.
To set the sticky bit on a world-writable directory DIR, run the following command:
$ sudo chmod +t DIR
        
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 directories present on the system. It is not a problem in most cases, but especially systems with a large number of directories can be affected. See https://access.redhat.com/articles/6999111.
Rationale:
Failing to set the sticky bit on public directories allows unauthorized users to delete files in the directory structure.

The only authorized public directories are those temporary directories supplied with the system, or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system, by users for temporary file storage (such as /tmp), and for directories requiring global read/write access.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dir_perms_world_writable_sticky_bits
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-001090
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
os-srgSRG-OS-000138-GPOS-00069
anssiR54
cis6.1.11
pcidss42.2.6, 2.2

Rule   Ensure No World-Writable Files Exist   [ref]

It is generally a good idea to remove global (other) write access to a file when it is discovered. However, check with documentation for specific applications before making changes. Also, monitor for recurring world-writable files, as these may be symptoms of a misconfigured application or user account. Finally, this applies to real files and not virtual files that are a part of pseudo file systems such as sysfs or procfs.
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 files present on the system. It is not a problem in most cases, but especially systems with a large number of files can be affected. See https://access.redhat.com/articles/6999111.
Rationale:
Data in world-writable files can be modified by any user on the system. In almost all circumstances, files can be configured using a combination of user and group permissions to support whatever legitimate access is needed without the risk caused by world-writable files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_unauthorized_world_writable
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
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
anssiR54
cis6.1.11
pcidss42.2.6, 2.2

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

FILTER_NODEV=$(awk '/nodev/ { print $2 }' /proc/filesystems | paste -sd,)
PARTITIONS=$(findmnt -n -l -k -it $FILTER_NODEV | awk '{ print $1 }')
for PARTITION in $PARTITIONS; do
  find "${PARTITION}" -xdev -type f -perm -002 -exec chmod o-w {} \; 2>/dev/null
done

# Ensure /tmp is also fixed whem tmpfs is used.
if grep "^tmpfs /tmp" /proc/mounts; then
  find /tmp -xdev -type f -perm -002 -exec chmod o-w {} \; 2>/dev/null
fi

Rule   Ensure All Files Are Owned by a Group   [ref]

If any file is not group-owned by a valid defined group, the cause of the lack of group-ownership must be investigated. Following this, those files should be deleted or assigned to an appropriate group. The groups need to be defined in /etc/group or in /usr/lib/group if nss-altfiles are configured to be used in /etc/nsswitch.conf. Locate the mount points related to local devices by the following command:
$ findmnt -n -l -k -it $(awk '/nodev/ { print $2 }' /proc/filesystems | paste -sd,)
For all mount points listed by the previous command, it is necessary to search for files which do not belong to a valid group using the following command:
$ sudo find MOUNTPOINT -xdev -nogroup 2>/dev/null
Warning:  This rule only considers local groups as valid groups. If you have your groups defined outside /etc/group or /usr/lib/group, the rule won't consider those.
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 files present on the system. It is not a problem in most cases, but especially systems with a large number of files can be affected. See https://access.redhat.com/articles/6999111.
Rationale:
Unowned files do not directly imply a security problem, but they are generally a sign that something is amiss. They may be caused by an intruder, by incorrect software installation or draft software removal, or by failure to remove all files belonging to a deleted account, or other similar cases. The files should be repaired so they will not cause problems when accounts are created in the future, and the cause should be discovered and addressed.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_ungroupowned
References:
cis-csc1, 11, 12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.02, DSS06.03, DSS06.06, DSS06.10
disaCCI-000366
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, 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
nistCM-6(a), AC-6(1)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.DS-5, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
anssiR53
cis6.1.12
pcidss42.2.6, 2.2

Rule   Ensure All Files Are Owned by a User   [ref]

If any files are not owned by a user, then the cause of their lack of ownership should be investigated. Following this, the files should be deleted or assigned to an appropriate user. Locate the mount points related to local devices by the following command:
$ findmnt -n -l -k -it $(awk '/nodev/ { print $2 }' /proc/filesystems | paste -sd,)
For all mount points listed by the previous command, it is necessary to search for files which do not belong to a valid user using the following command:
$ sudo find MOUNTPOINT -xdev -nouser 2>/dev/null
Warning:  For this rule to evaluate centralized user accounts, getent must be working properly so that running the command
getent passwd
returns a list of all users in your organization. If using the System Security Services Daemon (SSSD),
enumerate = true
must be configured in your organization's domain to return a complete list of users
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 files present on the system. It is not a problem in most cases, but especially systems with a large number of files can be affected. See https://access.redhat.com/articles/6999111.
Rationale:
Unowned files do not directly imply a security problem, but they are generally a sign that something is amiss. They may be caused by an intruder, by incorrect software installation or draft software removal, or by failure to remove all files belonging to a deleted account, or other similar cases. The files should be repaired so they will not cause problems when accounts are created in the future, and the cause should be discovered and addressed.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_files_unowned_by_user
References:
cis-csc11, 12, 13, 14, 15, 16, 18, 3, 5, 9
cobit5APO01.06, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.02, DSS06.03, DSS06.06
disaCCI-000366
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
nistCM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.AC-6, PR.DS-5, PR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
anssiR53
cis6.1.12
pcidss42.2.6, 2.2
Group   Restrict Dynamic Mounting and Unmounting of Filesystems   Group contains 6 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 Mounting of cramfs   [ref]

To configure the system to prevent the cramfs kernel module from being loaded, add the following line to the file /etc/modprobe.d/cramfs.conf:
install cramfs /bin/false
This effectively prevents usage of this uncommon filesystem. The cramfs filesystem type is a compressed read-only Linux filesystem embedded in small footprint systems. A cramfs image can be used without having to first decompress the image.
Rationale:
Removing support for unneeded filesystem types reduces the local attack surface of the server.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_kernel_module_cramfs_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.4.6
disaCCI-000381
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
os-srgSRG-OS-000095-GPOS-00049
cis1.1.1.3

Rule   Disable Mounting of freevxfs   [ref]

To configure the system to prevent the freevxfs kernel module from being loaded, add the following line to the file /etc/modprobe.d/freevxfs.conf:
install freevxfs /bin/false
This effectively prevents usage of this uncommon filesystem.
Rationale:
Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_kernel_module_freevxfs_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.4.6
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis1.1.1.4

Rule   Disable Mounting of hfs   [ref]

To configure the system to prevent the hfs kernel module from being loaded, add the following line to the file /etc/modprobe.d/hfs.conf:
install hfs /bin/false
This effectively prevents usage of this uncommon filesystem.
Rationale:
Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_kernel_module_hfs_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.4.6
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis1.1.1.6

Rule   Disable Mounting of hfsplus   [ref]

To configure the system to prevent the hfsplus kernel module from being loaded, add the following line to the file /etc/modprobe.d/hfsplus.conf:
install hfsplus /bin/false
This effectively prevents usage of this uncommon filesystem.
Rationale:
Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_kernel_module_hfsplus_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.4.6
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis1.1.1.7

Rule   Disable Mounting of jffs2   [ref]

To configure the system to prevent the jffs2 kernel module from being loaded, add the following line to the file /etc/modprobe.d/jffs2.conf:
install jffs2 /bin/false
This effectively prevents usage of this uncommon filesystem.
Rationale:
Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_kernel_module_jffs2_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
cui3.4.6
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis1.1.1.5

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/false
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
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-000778, CCI-001958, CCI-003959
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
cis1.1.9
pcidss43.4.2, 3.4
Group   Restrict Partition Mount Options   Group contains 19 rules
[ref]   System partitions can be mounted with certain options that limit what files on those partitions can do. These options are set in the /etc/fstab configuration file, and can be used to make certain types of malicious behavior more difficult.

Rule   Add nodev Option to /dev/shm   [ref]

The nodev mount option can be used to prevent creation of device files in /dev/shm. Legitimate character and block devices should not exist within temporary directories like /dev/shm. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_dev_shm_nodev
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.8.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ); then

function perform_remediation {
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /dev/shm)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type="tmpfs"
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo "tmpfs /dev/shm tmpfs defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/dev/shm"; then
        if mountpoint -q "/dev/shm"; then
            mount -o remount --target "/dev/shm"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /dev/shm: Check information associated to mountpoint'
  command: findmnt  '/dev/shm'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when: ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /dev/shm: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /dev/shm: If /dev/shm not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /dev/shm
    - tmpfs
    - tmpfs
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - ("" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /dev/shm: Make sure nodev option is part of the to /dev/shm
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /dev/shm: Ensure /dev/shm is mounted with nodev option'
  mount:
    path: /dev/shm
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("" |
    length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nodev
  - no_reboot_needed

Rule   Add noexec Option to /dev/shm   [ref]

The noexec mount option can be used to prevent binaries from being executed out of /dev/shm. It can be dangerous to allow the execution of binaries from world-writable temporary storage directories such as /dev/shm. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.
Rationale:
Allowing users to execute binaries from world-writable directories such as /dev/shm can expose the system to potential compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_dev_shm_noexec
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.8.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ); then

function perform_remediation {
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /dev/shm)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type="tmpfs"
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo "tmpfs /dev/shm tmpfs defaults,${previous_mount_opts}noexec 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "noexec"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,noexec|" /etc/fstab
    fi


    if mkdir -p "/dev/shm"; then
        if mountpoint -q "/dev/shm"; then
            mount -o remount --target "/dev/shm"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Check information associated to mountpoint'
  command: findmnt  '/dev/shm'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when: ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: If /dev/shm not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /dev/shm
    - tmpfs
    - tmpfs
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - ("" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Make sure noexec option is part of the to
    /dev/shm options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',noexec''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - mount_info is defined and "noexec" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /dev/shm: Ensure /dev/shm is mounted with noexec option'
  mount:
    path: /dev/shm
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("" |
    length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_noexec
  - no_reboot_needed

Rule   Add nosuid Option to /dev/shm   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /dev/shm. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.
Rationale:
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_dev_shm_nosuid
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.8.4

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ); then

function perform_remediation {
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /dev/shm)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type="tmpfs"
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo "tmpfs /dev/shm tmpfs defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/dev/shm"; then
        if mountpoint -q "/dev/shm"; then
            mount -o remount --target "/dev/shm"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /dev/shm: Check information associated to mountpoint'
  command: findmnt  '/dev/shm'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when: ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /dev/shm: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /dev/shm: If /dev/shm not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /dev/shm
    - tmpfs
    - tmpfs
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - ("" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /dev/shm: Make sure nosuid option is part of the to
    /dev/shm options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /dev/shm: Ensure /dev/shm is mounted with nosuid option'
  mount:
    path: /dev/shm
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("" |
    length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_dev_shm_nosuid
  - no_reboot_needed

Rule   Add nodev Option to /home   [ref]

The nodev mount option can be used to prevent device files from being created in /home. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /home.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_home_nodev
References:
disaCCI-001764
os-srgSRG-OS-000368-GPOS-00154
cis1.1.7.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/home" > /dev/null || findmnt --fstab "/home" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /home has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/home")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/home' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /home in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /home)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /home  defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/home"; then
        if mountpoint -q "/home"; then
            mount -o remount --target "/home"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - mount_option_home_nodev
  - no_reboot_needed
  - unknown_severity

- name: 'Add nodev Option to /home: Check information associated to mountpoint'
  command: findmnt --fstab '/home'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - mount_option_home_nodev
  - no_reboot_needed
  - unknown_severity

- name: 'Add nodev Option to /home: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - mount_option_home_nodev
  - no_reboot_needed
  - unknown_severity

- name: 'Add nodev Option to /home: If /home not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /home
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - mount_option_home_nodev
  - no_reboot_needed
  - unknown_severity

- name: 'Add nodev Option to /home: Make sure nodev option is part of the to /home
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - mount_option_home_nodev
  - no_reboot_needed
  - unknown_severity

- name: 'Add nodev Option to /home: Ensure /home is mounted with nodev option'
  mount:
    path: /home
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - mount_option_home_nodev
  - no_reboot_needed
  - unknown_severity

Rule   Add nosuid Option to /home   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /home. The SUID and SGID permissions should not be required in these user data directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /home.
Rationale:
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from user home directory partitions.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_home_nosuid
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-000366, CCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154, SRG-OS-000480-GPOS-00227
anssiR28
cis1.1.7.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/home" > /dev/null || findmnt --fstab "/home" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /home has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/home")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/home' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /home in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /home)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /home  defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/home"; then
        if mountpoint -q "/home"; then
            mount -o remount --target "/home"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_home_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /home: Check information associated to mountpoint'
  command: findmnt --fstab '/home'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_home_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /home: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_home_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /home: If /home not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /home
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_home_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /home: Make sure nosuid option is part of the to /home
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_home_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /home: Ensure /home is mounted with nosuid option'
  mount:
    path: /home
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/home" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_home_nosuid
  - no_reboot_needed

Rule   Add nodev Option to /tmp   [ref]

The nodev mount option can be used to prevent device files from being created in /tmp. Legitimate character and block devices should not exist within temporary directories like /tmp. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /tmp.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_tmp_nodev
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.2.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/tmp" > /dev/null || findmnt --fstab "/tmp" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /tmp has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/tmp")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/tmp' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /tmp in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /tmp)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /tmp  defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/tmp"; then
        if mountpoint -q "/tmp"; then
            mount -o remount --target "/tmp"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /tmp: Check information associated to mountpoint'
  command: findmnt --fstab '/tmp'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /tmp: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /tmp: If /tmp not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /tmp
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /tmp: Make sure nodev option is part of the to /tmp options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /tmp: Ensure /tmp is mounted with nodev option'
  mount:
    path: /tmp
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nodev
  - no_reboot_needed

Rule   Add noexec Option to /tmp   [ref]

The noexec mount option can be used to prevent binaries from being executed out of /tmp. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /tmp.
Rationale:
Allowing users to execute binaries from world-writable directories such as /tmp should never be necessary in normal operation and can expose the system to potential compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_tmp_noexec
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
anssiR28
cis1.1.2.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/tmp" > /dev/null || findmnt --fstab "/tmp" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /tmp has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/tmp")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/tmp' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /tmp in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /tmp)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /tmp  defaults,${previous_mount_opts}noexec 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "noexec"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,noexec|" /etc/fstab
    fi


    if mkdir -p "/tmp"; then
        if mountpoint -q "/tmp"; then
            mount -o remount --target "/tmp"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /tmp: Check information associated to mountpoint'
  command: findmnt --fstab '/tmp'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /tmp: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /tmp: If /tmp not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /tmp
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /tmp: Make sure noexec option is part of the to /tmp
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',noexec''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "noexec" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /tmp: Ensure /tmp is mounted with noexec option'
  mount:
    path: /tmp
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_noexec
  - no_reboot_needed

Rule   Add nosuid Option to /tmp   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /tmp. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /tmp.
Rationale:
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_tmp_nosuid
References:
cis-csc11, 13, 14, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS05.06, DSS06.06
disaCCI-001764
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.11.2.9, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.8.2.1, A.8.2.2, A.8.2.3, A.8.3.1, A.8.3.3, A.9.1.2
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
anssiR28
cis1.1.2.4

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/tmp" > /dev/null || findmnt --fstab "/tmp" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /tmp has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/tmp")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/tmp' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /tmp in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /tmp)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /tmp  defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/tmp"; then
        if mountpoint -q "/tmp"; then
            mount -o remount --target "/tmp"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /tmp: Check information associated to mountpoint'
  command: findmnt --fstab '/tmp'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /tmp: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /tmp: If /tmp not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /tmp
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /tmp: Make sure nosuid option is part of the to /tmp
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /tmp: Ensure /tmp is mounted with nosuid option'
  mount:
    path: /tmp
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_tmp_nosuid
  - no_reboot_needed

Rule   Add nodev Option to /var/log/audit   [ref]

The nodev mount option can be used to prevent device files from being created in /var/log/audit. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var/log/audit.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_log_audit_nodev
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.6.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/log/audit" > /dev/null || findmnt --fstab "/var/log/audit" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/log/audit has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/log/audit")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/log/audit' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/log/audit in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/log/audit)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/log/audit  defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/var/log/audit"; then
        if mountpoint -q "/var/log/audit"; then
            mount -o remount --target "/var/log/audit"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log/audit: Check information associated to mountpoint'
  command: findmnt --fstab '/var/log/audit'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log/audit: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log/audit: If /var/log/audit not mounted, craft
    mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/log/audit
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log/audit: Make sure nodev option is part of the
    to /var/log/audit options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log/audit: Ensure /var/log/audit is mounted with
    nodev option'
  mount:
    path: /var/log/audit
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nodev
  - no_reboot_needed

Rule   Add noexec Option to /var/log/audit   [ref]

The noexec mount option can be used to prevent binaries from being executed out of /var/log/audit. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /var/log/audit.
Rationale:
Allowing users to execute binaries from directories containing audit log files such as /var/log/audit should never be necessary in normal operation and can expose the system to potential compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_log_audit_noexec
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.6.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/log/audit" > /dev/null || findmnt --fstab "/var/log/audit" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/log/audit has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/log/audit")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/log/audit' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/log/audit in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/log/audit)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/log/audit  defaults,${previous_mount_opts}noexec 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "noexec"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,noexec|" /etc/fstab
    fi


    if mkdir -p "/var/log/audit"; then
        if mountpoint -q "/var/log/audit"; then
            mount -o remount --target "/var/log/audit"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log/audit: Check information associated to mountpoint'
  command: findmnt --fstab '/var/log/audit'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log/audit: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log/audit: If /var/log/audit not mounted, craft
    mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/log/audit
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log/audit: Make sure noexec option is part of the
    to /var/log/audit options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',noexec''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "noexec" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log/audit: Ensure /var/log/audit is mounted with
    noexec option'
  mount:
    path: /var/log/audit
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_noexec
  - no_reboot_needed

Rule   Add nosuid Option to /var/log/audit   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /var/log/audit. The SUID and SGID permissions should not be required in directories containing audit log files. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var/log/audit.
Rationale:
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from partitions designated for audit log files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_log_audit_nosuid
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.6.4

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/log/audit" > /dev/null || findmnt --fstab "/var/log/audit" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/log/audit has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/log/audit")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/log/audit' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/log/audit in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/log/audit)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/log/audit  defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/var/log/audit"; then
        if mountpoint -q "/var/log/audit"; then
            mount -o remount --target "/var/log/audit"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log/audit: Check information associated to mountpoint'
  command: findmnt --fstab '/var/log/audit'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log/audit: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log/audit: If /var/log/audit not mounted, craft
    mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/log/audit
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log/audit: Make sure nosuid option is part of the
    to /var/log/audit options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log/audit: Ensure /var/log/audit is mounted with
    nosuid option'
  mount:
    path: /var/log/audit
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log/audit" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_audit_nosuid
  - no_reboot_needed

Rule   Add nodev Option to /var/log   [ref]

The nodev mount option can be used to prevent device files from being created in /var/log. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var/log.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_log_nodev
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.5.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/log" > /dev/null || findmnt --fstab "/var/log" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/log has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/log")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/log' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/log in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/log)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/log  defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/var/log"; then
        if mountpoint -q "/var/log"; then
            mount -o remount --target "/var/log"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log: Check information associated to mountpoint'
  command: findmnt --fstab '/var/log'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log: If /var/log not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/log
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log: Make sure nodev option is part of the to /var/log
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/log: Ensure /var/log is mounted with nodev option'
  mount:
    path: /var/log
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nodev
  - no_reboot_needed

Rule   Add noexec Option to /var/log   [ref]

The noexec mount option can be used to prevent binaries from being executed out of /var/log. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /var/log.
Rationale:
Allowing users to execute binaries from directories containing log files such as /var/log should never be necessary in normal operation and can expose the system to potential compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_log_noexec
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
anssiR28
cis1.1.5.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/log" > /dev/null || findmnt --fstab "/var/log" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/log has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/log")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/log' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/log in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/log)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/log  defaults,${previous_mount_opts}noexec 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "noexec"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,noexec|" /etc/fstab
    fi


    if mkdir -p "/var/log"; then
        if mountpoint -q "/var/log"; then
            mount -o remount --target "/var/log"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log: Check information associated to mountpoint'
  command: findmnt --fstab '/var/log'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log: If /var/log not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/log
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log: Make sure noexec option is part of the to
    /var/log options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',noexec''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "noexec" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/log: Ensure /var/log is mounted with noexec option'
  mount:
    path: /var/log
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_noexec
  - no_reboot_needed

Rule   Add nosuid Option to /var/log   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /var/log. The SUID and SGID permissions should not be required in directories containing log files. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var/log.
Rationale:
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from partitions designated for log files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_log_nosuid
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
anssiR28
cis1.1.5.4

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/log" > /dev/null || findmnt --fstab "/var/log" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/log has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/log")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/log' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/log in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/log)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/log  defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/var/log"; then
        if mountpoint -q "/var/log"; then
            mount -o remount --target "/var/log"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log: Check information associated to mountpoint'
  command: findmnt --fstab '/var/log'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log: If /var/log not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/log
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log: Make sure nosuid option is part of the to
    /var/log options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/log: Ensure /var/log is mounted with nosuid option'
  mount:
    path: /var/log
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/log" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_log_nosuid
  - no_reboot_needed

Rule   Add nodev Option to /var   [ref]

The nodev mount option can be used to prevent device files from being created in /var. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_nodev
References:
disaCCI-001764
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-6, AC-6(1), MP-7
nist-csfPR.IP-1, PR.PT-2, PR.PT-3
os-srgSRG-OS-000368-GPOS-00154
cis1.1.3.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var" > /dev/null || findmnt --fstab "/var" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var  defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/var"; then
        if mountpoint -q "/var"; then
            mount -o remount --target "/var"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var: Check information associated to mountpoint'
  command: findmnt --fstab '/var'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var: If /var not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var: Make sure nodev option is part of the to /var options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var: Ensure /var is mounted with nodev option'
  mount:
    path: /var
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - NIST-800-53-AC-6
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nodev
  - no_reboot_needed

Rule   Add nosuid Option to /var   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /var. The SUID and SGID permissions should not be required for this directory. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var.
Rationale:
The presence of SUID and SGID executables should be tightly controlled.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_nosuid
References:
anssiR28
cis1.1.3.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var" > /dev/null || findmnt --fstab "/var" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var  defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/var"; then
        if mountpoint -q "/var"; then
            mount -o remount --target "/var"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var: Check information associated to mountpoint'
  command: findmnt --fstab '/var'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var: If /var not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var: Make sure nosuid option is part of the to /var
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var: Ensure /var is mounted with nosuid option'
  mount:
    path: /var
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_nosuid
  - no_reboot_needed

Rule   Add nodev Option to /var/tmp   [ref]

The nodev mount option can be used to prevent device files from being created in /var/tmp. Legitimate character and block devices should not exist within temporary directories like /var/tmp. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var/tmp.
Rationale:
The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_tmp_nodev
References:
disaCCI-001764
os-srgSRG-OS-000368-GPOS-00154
cis1.1.4.4

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/tmp" > /dev/null || findmnt --fstab "/var/tmp" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/tmp has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/tmp")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/tmp' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/tmp in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/tmp)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nodev)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/tmp  defaults,${previous_mount_opts}nodev 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nodev"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nodev|" /etc/fstab
    fi


    if mkdir -p "/var/tmp"; then
        if mountpoint -q "/var/tmp"; then
            mount -o remount --target "/var/tmp"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/tmp: Check information associated to mountpoint'
  command: findmnt --fstab '/var/tmp'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/tmp: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/tmp: If /var/tmp not mounted, craft mount_info manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/tmp
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/tmp: Make sure nodev option is part of the to /var/tmp
    options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nodev''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nodev" not in mount_info.options
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nodev
  - no_reboot_needed

- name: 'Add nodev Option to /var/tmp: Ensure /var/tmp is mounted with nodev option'
  mount:
    path: /var/tmp
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nodev
  - no_reboot_needed

Rule   Add noexec Option to /var/tmp   [ref]

The noexec mount option can be used to prevent binaries from being executed out of /var/tmp. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /var/tmp.
Rationale:
Allowing users to execute binaries from world-writable directories such as /var/tmp should never be necessary in normal operation and can expose the system to potential compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_tmp_noexec
References:
disaCCI-001764
os-srgSRG-OS-000368-GPOS-00154
anssiR28
cis1.1.4.2

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/tmp" > /dev/null || findmnt --fstab "/var/tmp" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/tmp has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/tmp")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/tmp' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/tmp in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/tmp)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/tmp  defaults,${previous_mount_opts}noexec 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "noexec"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,noexec|" /etc/fstab
    fi


    if mkdir -p "/var/tmp"; then
        if mountpoint -q "/var/tmp"; then
            mount -o remount --target "/var/tmp"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/tmp: Check information associated to mountpoint'
  command: findmnt --fstab '/var/tmp'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/tmp: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/tmp: If /var/tmp not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/tmp
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/tmp: Make sure noexec option is part of the to
    /var/tmp options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',noexec''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "noexec" not in mount_info.options
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_noexec
  - no_reboot_needed

- name: 'Add noexec Option to /var/tmp: Ensure /var/tmp is mounted with noexec option'
  mount:
    path: /var/tmp
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_noexec
  - no_reboot_needed

Rule   Add nosuid Option to /var/tmp   [ref]

The nosuid mount option can be used to prevent execution of setuid programs in /var/tmp. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var/tmp.
Rationale:
The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_mount_option_var_tmp_nosuid
References:
disaCCI-001764
os-srgSRG-OS-000368-GPOS-00154
anssiR28
cis1.1.4.3

Reboot:false
# Remediation is applicable only in certain platforms
if ( ! ( { rpm --quiet -q kernel ;} && { rpm --quiet -q rpm-ostree ;} && { rpm --quiet -q bootc ;} ) && ! ( [ -f /.dockerenv ] || [ -f /run/.containerenv ] ) ) && { findmnt --kernel "/var/tmp" > /dev/null || findmnt --fstab "/var/tmp" > /dev/null; }; then

function perform_remediation {
    
        # the mount point /var/tmp has to be defined in /etc/fstab
        # before this remediation can be executed. In case it is not defined, the
        # remediation aborts and no changes regarding the mount point are done.
        mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" "/var/tmp")"

    grep "$mount_point_match_regexp" -q /etc/fstab \
        || { echo "The mount point '/var/tmp' is not even in /etc/fstab, so we can't set up mount options" >&2;
                echo "Not remediating, because there is no record of /var/tmp in /etc/fstab" >&2; return 1; }
    


    mount_point_match_regexp="$(printf "^[[:space:]]*[^#].*[[:space:]]%s[[:space:]]" /var/tmp)"

    # If the mount point is not in /etc/fstab, get previous mount options from /etc/mtab
    if ! grep -q "$mount_point_match_regexp" /etc/fstab; then
        # runtime opts without some automatic kernel/userspace-added defaults
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/mtab | head -1 |  awk '{print $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//g;s/,$//")
        [ "$previous_mount_opts" ] && previous_mount_opts+=","
        # In iso9660 filesystems mtab could describe a "blocksize" value, this should be reflected in
        # fstab as "block".  The next variable is to satisfy shellcheck SC2050.
        fs_type=""
        if [  "$fs_type" == "iso9660" ] ; then
            previous_mount_opts=$(sed 's/blocksize=/block=/' <<< "$previous_mount_opts")
        fi
        echo " /var/tmp  defaults,${previous_mount_opts}nosuid 0 0" >> /etc/fstab
    # If the mount_opt option is not already in the mount point's /etc/fstab entry, add it
    elif ! grep "$mount_point_match_regexp" /etc/fstab | grep -q "nosuid"; then
        previous_mount_opts=$(grep "$mount_point_match_regexp" /etc/fstab | awk '{print $4}')
        sed -i "s|\(${mount_point_match_regexp}.*${previous_mount_opts}\)|\1,nosuid|" /etc/fstab
    fi


    if mkdir -p "/var/tmp"; then
        if mountpoint -q "/var/tmp"; then
            mount -o remount --target "/var/tmp"
        fi
    fi
}

perform_remediation

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

Complexity:low
Disruption:high
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/tmp: Check information associated to mountpoint'
  command: findmnt --fstab '/var/tmp'
  register: device_name
  failed_when: device_name.rc > 1
  changed_when: false
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/tmp: Create mount_info dictionary variable'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - '{{ device_name.stdout_lines[0].split() | list | lower }}'
  - '{{ device_name.stdout_lines[1].split() | list }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length > 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/tmp: If /var/tmp not mounted, craft mount_info
    manually'
  set_fact:
    mount_info: '{{ mount_info|default({})|combine({item.0: item.1}) }}'
  with_together:
  - - target
    - source
    - fstype
    - options
  - - /var/tmp
    - ''
    - ''
    - defaults
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - ("--fstab" | length == 0)
  - device_name.stdout is defined and device_name.stdout_lines is defined
  - (device_name.stdout | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/tmp: Make sure nosuid option is part of the to
    /var/tmp options'
  set_fact:
    mount_info: '{{ mount_info | combine( {''options'':''''~mount_info.options~'',nosuid''
      }) }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined and "nosuid" not in mount_info.options
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nosuid
  - no_reboot_needed

- name: 'Add nosuid Option to /var/tmp: Ensure /var/tmp is mounted with nosuid option'
  mount:
    path: /var/tmp
    src: '{{ mount_info.source }}'
    opts: '{{ mount_info.options }}'
    state: mounted
    fstype: '{{ mount_info.fstype }}'
  when:
  - ( not ( "kernel" in ansible_facts.packages and "rpm-ostree" in ansible_facts.packages
    and "bootc" in ansible_facts.packages ) and not ( ansible_virtualization_type
    in ["docker", "lxc", "openvz", "podman", "container"] ) )
  - '"/var/tmp" in ansible_mounts | map(attribute="mount") | list'
  - mount_info is defined
  - (device_name.stdout is defined and (device_name.stdout | length > 0)) or ("--fstab"
    | length == 0)
  tags:
  - configure_strategy
  - high_disruption
  - low_complexity
  - medium_severity
  - mount_option_var_tmp_nosuid
  - no_reboot_needed
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 2 rules
[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 dump backtraces   [ref]

The ProcessSizeMax option in [Coredump] section of /etc/systemd/coredump.conf specifies the maximum size in bytes of a core which will be processed. Core dumps exceeding this size may be stored, but the backtrace will not be generated.
Warning:  If the /etc/systemd/coredump.conf file does not already contain the [Coredump] section, the value will not be configured correctly.
Rationale:
A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers or system operators trying to debug problems. Enabling core dumps on production systems is not recommended, however there may be overriding operational requirements to enable advanced debuging. Permitting temporary enablement of core dumps during such situations should be reviewed through local needs and policy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_coredump_disable_backtraces
References:
disaCCI-000366
nistCM-6
pcidssReq-3.2
os-srgSRG-OS-000480-GPOS-00227
cis1.5.4
pcidss43.3.1.1, 3.3.1, 3.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q systemd; then

found=false

# set value in all files if they contain section or key
for f in $(echo -n "/etc/systemd/coredump.conf"); do
    if [ ! -e "$f" ]; then
        continue
    fi

    # find key in section and change value
    if grep -qzosP "[[:space:]]*\[Coredump\]([^\n\[]*\n+)+?[[:space:]]*ProcessSizeMax" "$f"; then

            sed -i "s/ProcessSizeMax[^(\n)]*/ProcessSizeMax=0/" "$f"

            found=true

    # find section and add key = value to it
    elif grep -qs "[[:space:]]*\[Coredump\]" "$f"; then

            sed -i "/[[:space:]]*\[Coredump\]/a ProcessSizeMax=0" "$f"

            found=true
    fi
done

# if section not in any file, append section with key = value to FIRST file in files parameter
if ! $found ; then
    file=$(echo "/etc/systemd/coredump.conf" | cut -f1 -d ' ')
    mkdir -p "$(dirname "$file")"

    echo -e "[Coredump]\nProcessSizeMax=0" >> "$file"

fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6
  - PCI-DSS-Req-3.2
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - coredump_disable_backtraces
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set 'ProcessSizeMax' to '0' in the [Coredump] section of '/etc/systemd/coredump.conf'
  ini_file:
    path: /etc/systemd/coredump.conf
    section: Coredump
    option: ProcessSizeMax
    value: '0'
    create: true
    mode: 420
  when: '"systemd" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6
  - PCI-DSS-Req-3.2
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - coredump_disable_backtraces
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Disable storing core dump   [ref]

The Storage option in [Coredump] sectionof /etc/systemd/coredump.conf can be set to none to disable storing core dumps permanently.
Warning:  If the /etc/systemd/coredump.conf file does not already contain the [Coredump] section, the value will not be configured correctly.
Rationale:
A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers or system operators trying to debug problems. Enabling core dumps on production systems is not recommended, however there may be overriding operational requirements to enable advanced debuging. Permitting temporary enablement of core dumps during such situations should be reviewed through local needs and policy.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_coredump_disable_storage
References:
disaCCI-000366
nistCM-6
pcidssReq-3.2
os-srgSRG-OS-000480-GPOS-00227
cis1.5.3
pcidss43.3.1.1, 3.3.1, 3.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q systemd; then

found=false

# set value in all files if they contain section or key
for f in $(echo -n "/etc/systemd/coredump.conf"); do
    if [ ! -e "$f" ]; then
        continue
    fi

    # find key in section and change value
    if grep -qzosP "[[:space:]]*\[Coredump\]([^\n\[]*\n+)+?[[:space:]]*Storage" "$f"; then

            sed -i "s/Storage[^(\n)]*/Storage=none/" "$f"

            found=true

    # find section and add key = value to it
    elif grep -qs "[[:space:]]*\[Coredump\]" "$f"; then

            sed -i "/[[:space:]]*\[Coredump\]/a Storage=none" "$f"

            found=true
    fi
done

# if section not in any file, append section with key = value to FIRST file in files parameter
if ! $found ; then
    file=$(echo "/etc/systemd/coredump.conf" | cut -f1 -d ' ')
    mkdir -p "$(dirname "$file")"

    echo -e "[Coredump]\nStorage=none" >> "$file"

fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6
  - PCI-DSS-Req-3.2
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - coredump_disable_storage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set 'Storage' to 'none' in the [Coredump] section of '/etc/systemd/coredump.conf'
  ini_file:
    path: /etc/systemd/coredump.conf
    section: Coredump
    option: Storage
    value: none
    create: true
    mode: 420
  when: '"systemd" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6
  - PCI-DSS-Req-3.2
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - coredump_disable_storage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
Group   Enable ExecShield   Group contains 1 rule
[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 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
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
anssiR9
cis1.5.1
pcidss43.3.1.1, 3.3.1, 3.3

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - 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
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_randomize_va_space

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*kernel.randomize_va_space.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - 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
  - PCI-DSSv4-3.3.1
  - 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: '"kernel" in ansible_facts.packages'
  tags:
  - 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
  - PCI-DSSv4-3.3.1
  - 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: '"kernel" in ansible_facts.packages'
  tags:
  - 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
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_randomize_va_space

Rule   Restrict usage of ptrace to descendant processes   [ref]

To set the runtime status of the kernel.yama.ptrace_scope kernel parameter, run the following command:
$ sudo sysctl -w kernel.yama.ptrace_scope=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.yama.ptrace_scope = 1
Rationale:
Unrestricted usage of ptrace allows compromised binaries to run ptrace on another processes of the user. Like this, the attacker can steal sensitive information from the target processes (e.g. SSH sessions, web browser, ...) without any additional assistance from the user (i.e. without resorting to phishing).
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_kernel_yama_ptrace_scope
References:
disaCCI-000366, CCI-001082
nistSC-7(10)
os-srgSRG-OS-000132-GPOS-00067, SRG-OS-000480-GPOS-00227
anssiR11
cis1.5.2

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-SC-7(10)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_yama_ptrace_scope

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    - /usr/lib/sysctl.d/
    contains: ^[\s]*kernel.yama.ptrace_scope.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-SC-7(10)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_yama_ptrace_scope

- name: Comment out any occurrences of kernel.yama.ptrace_scope from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*kernel.yama.ptrace_scope
    replace: '#kernel.yama.ptrace_scope'
  loop: '{{ find_sysctl_d.files }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-SC-7(10)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_yama_ptrace_scope

- name: Ensure sysctl kernel.yama.ptrace_scope is set to 1
  sysctl:
    name: kernel.yama.ptrace_scope
    value: '1'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-SC-7(10)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_kernel_yama_ptrace_scope
Group   SELinux   Group contains 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 Amazon Linux 2023, 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 Amazon Linux 2023 system, unless that system has unusual requirements which make a stronger policy appropriate.

Rule   Install libselinux Package   [ref]

The libselinux package can be installed with the following command:
$ sudo dnf install libselinux
Rationale:
Security-enhanced Linux is a feature of the Linux kernel and a number of utilities with enhanced security functionality designed to add mandatory access controls to Linux. The libselinux package contains the core library of the Security-enhanced Linux system.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_libselinux_installed
References:
cis1.6.1.1
pcidss41.2.6, 1.2


[[packages]]
name = "libselinux"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.6
  - enable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_libselinux_installed

- name: Ensure libselinux is installed
  package:
    name: libselinux
    state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.6
  - enable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_libselinux_installed

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

class install_libselinux {
  package { 'libselinux':
    ensure => 'installed',
  }
}

Rule   Uninstall mcstrans Package   [ref]

The mcstransd daemon provides category label information to client processes requesting information. The label translations are defined in /etc/selinux/targeted/setrans.conf. The mcstrans package can be removed with the following command:
$ sudo dnf remove mcstrans
Rationale:
Since this service is not used very often, disable it to reduce the amount of potentially vulnerable code running on the system.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_mcstrans_removed
References:
cis1.6.1.8

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

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

if rpm -q --quiet "mcstrans" ; then
dnf remove -y --noautoremove "mcstrans"
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_mcstrans_removed

- name: Ensure mcstrans is removed
  package:
    name: mcstrans
    state: absent
  when: '"kernel" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_mcstrans_removed

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

class remove_mcstrans {
  package { 'mcstrans':
    ensure => 'purged',
  }
}

Rule   Uninstall setroubleshoot Package   [ref]

The SETroubleshoot service notifies desktop users of SELinux denials. The service provides information around configuration errors, unauthorized intrusions, and other potential errors. The setroubleshoot package can be removed with the following command:
$ sudo dnf remove setroubleshoot
Rationale:
The SETroubleshoot service is an unnecessary daemon to have running on a server, especially if X Windows is removed or disabled.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_setroubleshoot_removed
References:
anssiR49
cis1.6.1.7

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

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

if rpm -q --quiet "setroubleshoot" ; then
dnf remove -y --noautoremove "setroubleshoot"
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_setroubleshoot_removed

- name: Ensure setroubleshoot is removed
  package:
    name: setroubleshoot
    state: absent
  when: '"kernel" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_setroubleshoot_removed

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

class remove_setroubleshoot {
  package { 'setroubleshoot':
    ensure => 'purged',
  }
}

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
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
cis1.6.1.2
pcidss41.2.6, 1.2

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
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
cis1.6.1.6
pcidss41.2.6, 1.2

Rule   Ensure SELinux is Not Disabled   [ref]

The SELinux state should be set to enforcing or permissive at system boot time. In the file /etc/selinux/config, add or correct the following line to configure the system to boot into enforcing or permissive mode:
SELINUX=enforcing
OR
SELINUX=permissive
Warning:  In case the SELinux is "disabled", the automated remediation will adopt a more conservative approach and set it to "permissive" in order to avoid any system disruption and give the administrator the opportunity to assess the impact and necessary efforts before setting it to "enforcing", which is strongly recommended.
Rationale:
Running SELinux in disabled mode is strongly discouraged. It prevents enforcing the SELinux controls without a system reboot. It also avoids labeling any persistent objects such as files, making it difficult to enable SELinux in the future.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_selinux_not_disabled
References:
cis1.6.1.4

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

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=permissive" >> "/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

Complexity:low
Disruption:low
Reboot:true
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - high_severity
  - low_complexity
  - low_disruption
  - reboot_required
  - restrict_strategy
  - selinux_not_disabled

- name: Ensure SELinux is Not Disabled
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/selinux/config
      create: true
      regexp: (?i)^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: (?i)^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: (?i)^SELINUX=
      line: SELINUX=permissive
      state: present
  when: '"kernel" in ansible_facts.packages'
  tags:
  - high_severity
  - low_complexity
  - low_disruption
  - reboot_required
  - restrict_strategy
  - selinux_not_disabled

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
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-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
anssiR46, R64
bsiAPP.4.4.A4, SYS.1.6.A3, SYS.1.6.A18, SYS.1.6.A21
cis1.6.1.3
pcidss41.2.6, 1.2
Group   Services   Group contains 39 groups and 79 rules
[ref]   The best protection against vulnerable software is running less software. This section describes how to review the software which Amazon Linux 2023 installs on a system and disable software which is not needed. It then enumerates the software packages installed on a default Amazon Linux 2023 system and provides guidance about which ones can be safely disabled.

Amazon Linux 2023 provides a convenient minimal install option that essentially installs the bare necessities for a functional system. When building Amazon Linux 2023 systems, it is highly recommended to select the minimal packages and then build up the system from there.
Group   Avahi Server   Group contains 1 group and 1 rule
[ref]   The Avahi daemon implements the DNS Service Discovery and Multicast DNS protocols, which provide service and host discovery on a network. It allows a system to automatically identify resources on the network, such as printers or web servers. This capability is also known as mDNSresponder and is a major part of Zeroconf networking.
Group   Disable Avahi Server if Possible   Group contains 1 rule
[ref]   Because the Avahi daemon service keeps an open network port, it is subject to network attacks. Disabling it can reduce the system's vulnerability to such attacks.

Rule   Uninstall avahi Server Package   [ref]

If the system does not need to have an Avahi server which implements the DNS Service Discovery and Multicast DNS protocols, the avahi-autoipd and avahi packages can be uninstalled.
Rationale:
Automatic discovery of network services is not normally required for system functionality. It is recommended to remove this package to reduce the potential attack surface.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_avahi_removed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
disaCCI-000366
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis2.2.2

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

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

if rpm -q --quiet "avahi" ; then
dnf remove -y --noautoremove "avahi"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure avahi is removed
  package:
    name: avahi
    state: absent
  tags:
  - 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
  - package_avahi_removed

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

class remove_avahi {
  package { 'avahi':
    ensure => 'purged',
  }
}
Group   Cron and At Daemons   Group contains 1 group and 28 rules
[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.
Group   Restrict at and cron to Authorized Users if Necessary   Group contains 9 rules
[ref]   The /etc/cron.allow and /etc/at.allow files contain lists of users who are allowed to use cron and at to delay execution of processes. If these files exist and if the corresponding files /etc/cron.deny and /etc/at.deny do not exist, then only users listed in the relevant allow files can run the crontab and at commands to submit jobs to be run at scheduled intervals. On many systems, only the system administrator needs the ability to schedule jobs. Note that even if a given user is not listed in cron.allow, cron jobs can still be run as that user. The cron.allow file controls only administrative access to the crontab command for scheduling and modifying cron jobs.

To restrict at and cron to only authorized users:
  • Remove the cron.deny file:
    $ sudo rm /etc/cron.deny
  • Edit /etc/cron.allow, adding one line for each user allowed to use the crontab command to create cron jobs.
  • Remove the at.deny file:
    $ sudo rm /etc/at.deny
  • Edit /etc/at.allow, adding one line for each user allowed to use the at command to create at jobs.

Rule   Ensure that /etc/at.deny does not exist   [ref]

The file /etc/at.deny should not exist. Use /etc/at.allow instead.
Rationale:
Access to at should be restricted. It is easier to manage an allow list than a deny list.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_at_deny_not_exist
References:
cis4.1.9
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

if [[ -f  /etc/at.deny ]]; then
        rm /etc/at.deny
    fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - disable_strategy
  - file_at_deny_not_exist
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Remove /etc/at.deny
  file:
    path: /etc/at.deny
    state: absent
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - disable_strategy
  - file_at_deny_not_exist
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Ensure that /etc/cron.allow exists   [ref]

The file /etc/cron.allow should exist and should be used instead of /etc/cron.deny.
Rationale:
Access to crontab should be restricted. It is easier to manage an allow list than a deny list. Therefore, /etc/cron.allow needs to be created and used instead of /etc/cron.deny. Regardless of the existence of any of these files, the root administrative user is always allowed to setup a crontab.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_cron_allow_exists
References:
cis4.1.8

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

touch /etc/cron.allow
    chown 0 /etc/cron.allow
    chmod 0600 /etc/cron.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - file_cron_allow_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Add empty /etc/cron.allow
  file:
    path: /etc/cron.allow
    state: touch
    owner: '0'
    mode: '0600'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - disable_strategy
  - file_cron_allow_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Ensure that /etc/cron.deny does not exist   [ref]

The file /etc/cron.deny should not exist. Use /etc/cron.allow instead.
Rationale:
Access to cron should be restricted. It is easier to manage an allow list than a deny list.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_cron_deny_not_exist
References:
cis4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

if [[ -f  /etc/cron.deny ]]; then
        rm /etc/cron.deny
    fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - disable_strategy
  - file_cron_deny_not_exist
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Remove /etc/cron.deny
  file:
    path: /etc/cron.deny
    state: absent
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - disable_strategy
  - file_cron_deny_not_exist
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns /etc/at.allow file   [ref]

If /etc/at.allow exists, it must be group-owned by root. To properly set the group owner of /etc/at.allow, run the command:
$ sudo chgrp root /etc/at.allow
Rationale:
If the owner of the at.allow file is not set to root, the possibility exists for an unauthorized user to view or edit sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_at_allow
References:
cis4.1.9
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chgrp 0 /etc/at.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/at.allow
  stat:
    path: /etc/at.allow
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/at.allow
  file:
    path: /etc/at.allow
    group: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns /etc/cron.allow file   [ref]

If /etc/cron.allow exists, it must be group-owned by root. To properly set the group owner of /etc/cron.allow, run the command:
$ sudo chgrp root /etc/cron.allow
Rationale:
If the owner of the cron.allow file is not set to root, the possibility exists for an unauthorized user to view or edit sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_cron_allow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chgrp 0 /etc/cron.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/cron.allow
  stat:
    path: /etc/cron.allow
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/cron.allow
  file:
    path: /etc/cron.allow
    group: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns /etc/at.allow file   [ref]

If /etc/at.allow exists, it must be owned by root. To properly set the owner of /etc/at.allow, run the command:
$ sudo chown root /etc/at.allow 
Rationale:
If the owner of the at.allow file is not set to root, the possibility exists for an unauthorized user to view or edit sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_at_allow
References:
cis4.1.9
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chown 0 /etc/at.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/at.allow
  stat:
    path: /etc/at.allow
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/at.allow
  file:
    path: /etc/at.allow
    owner: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify User Who Owns /etc/cron.allow file   [ref]

If /etc/cron.allow exists, it must be owned by root. To properly set the owner of /etc/cron.allow, run the command:
$ sudo chown root /etc/cron.allow 
Rationale:
If the owner of the cron.allow file is not set to root, the possibility exists for an unauthorized user to view or edit sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_cron_allow
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chown 0 /etc/cron.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/cron.allow
  stat:
    path: /etc/cron.allow
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/cron.allow
  file:
    path: /etc/cron.allow
    owner: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on /etc/at.allow file   [ref]

If /etc/at.allow exists, it must have permissions 0640 or more restrictive. To properly set the permissions of /etc/at.allow, run the command:
$ sudo chmod 0640 /etc/at.allow
Rationale:
If the permissions of the at.allow file are not set to 0640 or more restrictive, the possibility exists for an unauthorized user to view or edit sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_at_allow
References:
cis4.1.9
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chmod u-xs,g-xws,o-xwrt /etc/at.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/at.allow
  stat:
    path: /etc/at.allow
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwrt on /etc/at.allow
  file:
    path: /etc/at.allow
    mode: u-xs,g-xws,o-xwrt
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_at_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on /etc/cron.allow file   [ref]

If /etc/cron.allow exists, it must have permissions 0640 or more restrictive. To properly set the permissions of /etc/cron.allow, run the command:
$ sudo chmod 0640 /etc/cron.allow
Rationale:
If the permissions of the cron.allow file are not set to 0640 or more restrictive, the possibility exists for an unauthorized user to view or edit sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_cron_allow
References:
os-srgSRG-OS-000480-GPOS-00227
cis4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chmod u-xs,g-xws,o-xwrt /etc/cron.allow

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/cron.allow
  stat:
    path: /etc/cron.allow
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwrt on /etc/cron.allow
  file:
    path: /etc/cron.allow
    mode: u-xs,g-xws,o-xwrt
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_allow
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

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
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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_crond_enabled

- 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: '"kernel" in ansible_facts.packages'
  tags:
  - 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',
  }
}

Rule   Verify Group Who Owns cron.d   [ref]

To properly set the group owner of /etc/cron.d, run the command:
$ sudo chgrp root /etc/cron.d
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_cron_d
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.d/ -maxdepth 1 -type d -exec chgrp -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/cron.d/
  file:
    path: /etc/cron.d/
    state: directory
    group: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns cron.daily   [ref]

To properly set the group owner of /etc/cron.daily, run the command:
$ sudo chgrp root /etc/cron.daily
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_cron_daily
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.daily/ -maxdepth 1 -type d -exec chgrp -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/cron.daily/
  file:
    path: /etc/cron.daily/
    state: directory
    group: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns cron.hourly   [ref]

To properly set the group owner of /etc/cron.hourly, run the command:
$ sudo chgrp root /etc/cron.hourly
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_cron_hourly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.hourly/ -maxdepth 1 -type d -exec chgrp -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/cron.hourly/
  file:
    path: /etc/cron.hourly/
    state: directory
    group: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns cron.monthly   [ref]

To properly set the group owner of /etc/cron.monthly, run the command:
$ sudo chgrp root /etc/cron.monthly
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_cron_monthly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.monthly/ -maxdepth 1 -type d -exec chgrp -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/cron.monthly/
  file:
    path: /etc/cron.monthly/
    state: directory
    group: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns cron.weekly   [ref]

To properly set the group owner of /etc/cron.weekly, run the command:
$ sudo chgrp root /etc/cron.weekly
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_cron_weekly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.weekly/ -maxdepth 1 -type d -exec chgrp -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/cron.weekly/
  file:
    path: /etc/cron.weekly/
    state: directory
    group: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Who Owns Crontab   [ref]

To properly set the group owner of /etc/crontab, run the command:
$ sudo chgrp root /etc/crontab
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_crontab
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chgrp 0 /etc/crontab

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/crontab
  stat:
    path: /etc/crontab
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/crontab
  file:
    path: /etc/crontab
    group: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_groupowner_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on cron.d   [ref]

To properly set the owner of /etc/cron.d, run the command:
$ sudo chown root /etc/cron.d 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct user to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_cron_d
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.d/ -maxdepth 1 -type d -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on directory /etc/cron.d/
  file:
    path: /etc/cron.d/
    state: directory
    owner: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on cron.daily   [ref]

To properly set the owner of /etc/cron.daily, run the command:
$ sudo chown root /etc/cron.daily 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct user to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_cron_daily
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.daily/ -maxdepth 1 -type d -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on directory /etc/cron.daily/
  file:
    path: /etc/cron.daily/
    state: directory
    owner: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on cron.hourly   [ref]

To properly set the owner of /etc/cron.hourly, run the command:
$ sudo chown root /etc/cron.hourly 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct user to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_cron_hourly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.hourly/ -maxdepth 1 -type d -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on directory /etc/cron.hourly/
  file:
    path: /etc/cron.hourly/
    state: directory
    owner: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on cron.monthly   [ref]

To properly set the owner of /etc/cron.monthly, run the command:
$ sudo chown root /etc/cron.monthly 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct user to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_cron_monthly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.monthly/ -maxdepth 1 -type d -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on directory /etc/cron.monthly/
  file:
    path: /etc/cron.monthly/
    state: directory
    owner: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on cron.weekly   [ref]

To properly set the owner of /etc/cron.weekly, run the command:
$ sudo chown root /etc/cron.weekly 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct user to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_cron_weekly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.weekly/ -maxdepth 1 -type d -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on directory /etc/cron.weekly/
  file:
    path: /etc/cron.weekly/
    state: directory
    owner: '0'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on crontab   [ref]

To properly set the owner of /etc/crontab, run the command:
$ sudo chown root /etc/crontab 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct user to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_crontab
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chown 0 /etc/crontab

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/crontab
  stat:
    path: /etc/crontab
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/crontab
  file:
    path: /etc/crontab
    owner: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_owner_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on cron.d   [ref]

To properly set the permissions of /etc/cron.d, run the command:
$ sudo chmod 0700 /etc/cron.d
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should have the correct access rights to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_cron_d
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.d/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt -type d -exec chmod u-s,g-xwrs,o-xwrt {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/cron.d/ file(s)
  command: 'find -H /etc/cron.d/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt  -type d '
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/cron.d/ file(s)
  file:
    path: '{{ item }}'
    mode: u-s,g-xwrs,o-xwrt
    state: directory
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_d
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on cron.daily   [ref]

To properly set the permissions of /etc/cron.daily, run the command:
$ sudo chmod 0700 /etc/cron.daily
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should have the correct access rights to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_cron_daily
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.daily/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt -type d -exec chmod u-s,g-xwrs,o-xwrt {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/cron.daily/ file(s)
  command: 'find -H /etc/cron.daily/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt  -type d '
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/cron.daily/ file(s)
  file:
    path: '{{ item }}'
    mode: u-s,g-xwrs,o-xwrt
    state: directory
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_daily
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on cron.hourly   [ref]

To properly set the permissions of /etc/cron.hourly, run the command:
$ sudo chmod 0700 /etc/cron.hourly
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should have the correct access rights to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_cron_hourly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.hourly/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt -type d -exec chmod u-s,g-xwrs,o-xwrt {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/cron.hourly/ file(s)
  command: 'find -H /etc/cron.hourly/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt  -type
    d '
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/cron.hourly/ file(s)
  file:
    path: '{{ item }}'
    mode: u-s,g-xwrs,o-xwrt
    state: directory
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_hourly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on cron.monthly   [ref]

To properly set the permissions of /etc/cron.monthly, run the command:
$ sudo chmod 0700 /etc/cron.monthly
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should have the correct access rights to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_cron_monthly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.monthly/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt -type d -exec chmod u-s,g-xwrs,o-xwrt {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/cron.monthly/ file(s)
  command: 'find -H /etc/cron.monthly/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt  -type
    d '
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/cron.monthly/ file(s)
  file:
    path: '{{ item }}'
    mode: u-s,g-xwrs,o-xwrt
    state: directory
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_monthly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on cron.weekly   [ref]

To properly set the permissions of /etc/cron.weekly, run the command:
$ sudo chmod 0700 /etc/cron.weekly
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should have the correct access rights to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_cron_weekly
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -H /etc/cron.weekly/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt -type d -exec chmod u-s,g-xwrs,o-xwrt {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/cron.weekly/ file(s)
  command: 'find -H /etc/cron.weekly/ -maxdepth 1 -perm /u+s,g+xwrs,o+xwrt  -type
    d '
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/cron.weekly/ file(s)
  file:
    path: '{{ item }}'
    mode: u-s,g-xwrs,o-xwrt
    state: directory
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_cron_weekly
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on crontab   [ref]

To properly set the permissions of /etc/crontab, run the command:
$ sudo chmod 0600 /etc/crontab
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should have the correct access rights to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_crontab
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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
os-srgSRG-OS-000480-GPOS-00227
cis4.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chmod u-xs,g-xwrs,o-xwrt /etc/crontab

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/crontab
  stat:
    path: /etc/crontab
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /etc/crontab
  file:
    path: /etc/crontab
    mode: u-xs,g-xwrs,o-xwrt
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_crontab
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
Group   DHCP   Group contains 1 group and 1 rule
[ref]   The Dynamic Host Configuration Protocol (DHCP) allows systems to request and obtain an IP address and other configuration parameters from a server.

This guide recommends configuring networking on clients by manually editing the appropriate files under /etc/sysconfig. Use of DHCP can make client systems vulnerable to compromise by rogue DHCP servers, and should be avoided unless necessary. If using DHCP is necessary, however, there are best practices that should be followed to minimize security risk.
Group   Disable DHCP Server   Group contains 1 rule
[ref]   The DHCP server dhcpd is not installed or activated by default. If the software was installed and activated, but the system does not need to act as a DHCP server, it should be disabled and removed.

Rule   Uninstall DHCP Server Package   [ref]

If the system does not need to act as a DHCP server, the dhcp package can be uninstalled. The dhcp package can be removed with the following command:
$ sudo dnf remove dhcp
Rationale:
Removing the DHCP server ensures that it cannot be easily or accidentally reactivated and disrupt network operation.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_dhcp_removed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
disaCCI-000366
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
anssiR62
cis2.2.4
pcidss42.2.4, 2.2

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

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

if rpm -q --quiet "dhcp" ; then
dnf remove -y --noautoremove "dhcp"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure dhcp is removed
  package:
    name: dhcp
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_dhcp_removed

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

class remove_dhcp {
  package { 'dhcp':
    ensure => 'purged',
  }
}
Group   DNS Server   Group contains 1 group and 2 rules
[ref]   Most organizations have an operational need to run at least one nameserver. However, there are many common attacks involving DNS server software, and this server software should be disabled on any system on which it is not needed.
Group   Disable DNS Server   Group contains 1 rule
[ref]   DNS software should be disabled on any systems which does not need to be a nameserver. Note that the BIND DNS server software is not installed on Amazon Linux 2023 by default. The remainder of this section discusses secure configuration of systems which must be nameservers.

Rule   Uninstall bind Package   [ref]

The named service is provided by the bind package. The bind package can be removed with the following command:
$ sudo dnf remove bind
Rationale:
If there is no need to make DNS server software available, removing it provides a safeguard against its activation.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_bind_removed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
disaCCI-000366
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis2.2.5

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

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

if rpm -q --quiet "bind" ; then
dnf remove -y --noautoremove "bind"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure bind is removed
  package:
    name: bind
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_bind_removed

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

class remove_bind {
  package { 'bind':
    ensure => 'purged',
  }
}

Rule   Uninstall dnsmasq Package   [ref]

dnsmasq is a lightweight tool that provides DNS caching, DNS forwarding and DHCP (Dynamic Host Configuration Protocol) services.
The dnsmasq package can be removed with the following command:
$ sudo dnf remove dnsmasq
Rationale:
Unless a system is specifically designated to act as a DNS caching, DNS forwarding and/or DHCP server, it is recommended that the package be removed to reduce the potential attack surface.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_dnsmasq_removed
References:
cis2.2.14

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

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

if rpm -q --quiet "dnsmasq" ; then
dnf remove -y --noautoremove "dnsmasq"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure dnsmasq is removed
  package:
    name: dnsmasq
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_dnsmasq_removed

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

class remove_dnsmasq {
  package { 'dnsmasq':
    ensure => 'purged',
  }
}
Group   FTP Server   Group contains 1 group and 2 rules
[ref]   FTP is a common method for allowing remote access to files. Like telnet, the FTP protocol is unencrypted, which means that passwords and other data transmitted during the session can be captured and that the session is vulnerable to hijacking. Therefore, running the FTP server software is not recommended.

However, there are some FTP server configurations which may be appropriate for some environments, particularly those which allow only read-only anonymous access as a means of downloading data available to the public.
Group   Disable vsftpd if Possible   Group contains 1 rule
[ref]   To minimize attack surface, disable vsftpd if at all possible.

Rule   Uninstall vsftpd Package   [ref]

The vsftpd package can be removed with the following command:
 $ sudo dnf remove vsftpd
Rationale:
Removing the vsftpd package decreases the risk of its accidental activation.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_vsftpd_removed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
disaCCI-000366, CCI-000197, CCI-000381
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-7(a), CM-7(b), CM-6(a), IA-5(1)(c), IA-5(1).1(v), CM-7, CM-7.1(ii)
nist-csfPR.IP-1, PR.PT-3
os-srgSRG-OS-000074-GPOS-00042, SRG-OS-000095-GPOS-00049, SRG-OS-000480-GPOS-00227
cis2.2.6

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

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

if rpm -q --quiet "vsftpd" ; then
dnf remove -y --noautoremove "vsftpd"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure vsftpd is removed
  package:
    name: vsftpd
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-CM-7.1(ii)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(1).1(v)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_vsftpd_removed

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

class remove_vsftpd {
  package { 'vsftpd':
    ensure => 'purged',
  }
}

Rule   Remove ftp Package   [ref]

FTP (File Transfer Protocol) is a traditional and widely used standard tool for transferring files between a server and clients over a network, especially where no authentication is necessary (permits anonymous users to connect to a server).
The ftp package can be removed with the following command:
$ sudo dnf remove ftp
Rationale:
FTP does not protect the confidentiality of data or authentication credentials. It is recommended SFTP be used if file transfer is required. Unless there is a need to run the system as a FTP server (for example, to allow anonymous downloads), it is recommended that the package be removed to reduce the potential attack surface.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_ftp_removed
References:
cis2.3.3
pcidss42.2.4, 2.2

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

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

if rpm -q --quiet "ftp" ; then
dnf remove -y --noautoremove "ftp"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure ftp is removed
  package:
    name: ftp
    state: absent
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_ftp_removed

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

class remove_ftp {
  package { 'ftp':
    ensure => 'purged',
  }
}
Group   Web Server   Group contains 2 groups and 2 rules
[ref]   The web server is responsible for providing access to content via the HTTP protocol. Web servers represent a significant security risk because:

  • The HTTP port is commonly probed by malicious sources
  • Web server software is very complex, and includes a long history of vulnerabilities
  • The HTTP protocol is unencrypted and vulnerable to passive monitoring


The system's default web server software is Apache 2 and is provided in the RPM package httpd.
Group   Disable Apache if Possible   Group contains 1 rule
[ref]   If Apache was installed and activated, but the system does not need to act as a web server, then it should be disabled and removed from the system.

Rule   Uninstall httpd Package   [ref]

The httpd package can be removed with the following command:
$ sudo dnf remove httpd
Rationale:
If there is no need to make the web server software available, removing it provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_httpd_removed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis2.2.8

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

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

if rpm -q --quiet "httpd" ; then
dnf remove -y --noautoremove "httpd"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure httpd is removed
  package:
    name: httpd
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_httpd_removed
  - unknown_severity

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

class remove_httpd {
  package { 'httpd':
    ensure => 'purged',
  }
}
Group   Disable NGINX if Possible   Group contains 1 rule
[ref]   If NGINX was installed and activated, but the system does not need to act as a web server, then it should be removed from the system.

Rule   Uninstall nginx Package   [ref]

The nginx package can be removed with the following command:
$ sudo dnf remove nginx
Rationale:
If there is no need to make the web server software available, removing it provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_nginx_removed
References:
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis2.2.8

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

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

if rpm -q --quiet "nginx" ; then
dnf remove -y --noautoremove "nginx"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure nginx is removed
  package:
    name: nginx
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_nginx_removed
  - unknown_severity

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

class remove_nginx {
  package { 'nginx':
    ensure => 'purged',
  }
}
Group   IMAP and POP3 Server   Group contains 2 groups and 2 rules
[ref]   Dovecot provides IMAP and POP3 services. It is not installed by default. The project page at http://www.dovecot.org contains more detailed information about Dovecot configuration.
Group   Disable Cyrus IMAP   Group contains 1 rule
[ref]   If the system does not need to operate as an IMAP or POP3 server, the Cyrus IMAP software should be removed.

Rule   Uninstall cyrus-imapd Package   [ref]

The cyrus-imapd package can be removed with the following command:
$ sudo dnf remove cyrus-imapd
Rationale:
If there is no need to make the cyrus-imapd software available, removing it provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_cyrus-imapd_removed
References:
cis2.2.9

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

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

if rpm -q --quiet "cyrus-imapd" ; then
dnf remove -y --noautoremove "cyrus-imapd"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure cyrus-imapd is removed
  package:
    name: cyrus-imapd
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_cyrus-imapd_removed
  - unknown_severity

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_cyrus-imapd

class remove_cyrus-imapd {
  package { 'cyrus-imapd':
    ensure => 'purged',
  }
}
Group   Disable Dovecot   Group contains 1 rule
[ref]   If the system does not need to operate as an IMAP or POP3 server, the dovecot software should be disabled and removed.

Rule   Uninstall dovecot Package   [ref]

The dovecot package can be removed with the following command:
$ sudo dnf remove dovecot
Rationale:
If there is no need to make the Dovecot software available, removing it provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_dovecot_removed
References:
cis2.2.9

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

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

if rpm -q --quiet "dovecot" ; then
dnf remove -y --noautoremove "dovecot"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure dovecot is removed
  package:
    name: dovecot
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_dovecot_removed
  - unknown_severity

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

class remove_dovecot {
  package { 'dovecot':
    ensure => 'purged',
  }
}
Group   LDAP   Group contains 1 group and 1 rule
[ref]   LDAP is a popular directory service, that is, a standardized way of looking up information from a central database. Amazon Linux 2023 includes software that enables a system to act as both an LDAP client and server.
Group   Configure OpenLDAP Clients   Group contains 1 rule
[ref]   This section provides information on which security settings are important to configure in OpenLDAP clients by manually editing the appropriate configuration files. Amazon Linux 2023 provides an automated configuration tool called authconfig and a graphical wrapper for authconfig called system-config-authentication. However, these tools do not provide as much control over configuration as manual editing of configuration files. The authconfig tools do not allow you to specify locations of SSL certificate files, which is useful when trying to use SSL cleanly across several protocols. Installation and configuration of OpenLDAP on Amazon Linux 2023 is available at
Warning:  Before configuring any system to be an LDAP client, ensure that a working LDAP server is present on the network.

Rule   Ensure LDAP client is not installed   [ref]

The Lightweight Directory Access Protocol (LDAP) is a service that provides a method for looking up information from a central database. The openldap-clients package can be removed with the following command:
$ sudo dnf remove openldap-clients
Rationale:
If the system does not need to act as an LDAP client, it is recommended that the software is removed to reduce the potential attack surface.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_openldap-clients_removed
References:
cis2.3.2

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

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

if rpm -q --quiet "openldap-clients" ; then
dnf remove -y --noautoremove "openldap-clients"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure openldap-clients is removed
  package:
    name: openldap-clients
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_openldap-clients_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_openldap-clients

class remove_openldap-clients {
  package { 'openldap-clients':
    ensure => 'purged',
  }
}
Group   Mail Server Software   Group contains 1 group and 2 rules
[ref]   Mail servers are used to send and receive email over the network. Mail is a very common service, and Mail Transfer Agents (MTAs) are obvious targets of network attack. Ensure that systems are not running MTAs unnecessarily, and configure needed MTAs as defensively as possible.

Very few systems at any site should be configured to directly receive email over the network. Users should instead use mail client programs to retrieve email from a central server that supports protocols such as IMAP or POP3. However, it is normal for most systems to be independently capable of sending email, for instance so that cron jobs can report output to an administrator. Most MTAs, including Postfix, support a submission-only mode in which mail can be sent from the local system to a central site MTA (or directly delivered to a local account), but the system still cannot receive mail directly over a network.

The alternatives program in Amazon Linux 2023 permits selection of other mail server software (such as Sendmail), but Postfix is the default and is preferred. Postfix was coded with security in mind and can also be more effectively contained by SELinux as its modular design has resulted in separate processes performing specific actions. More information is available on its website, http://www.postfix.org.
Group   Configure SMTP For Mail Clients   Group contains 1 rule
[ref]   This section discusses settings for Postfix in a submission-only e-mail configuration.

Rule   Disable Postfix Network Listening   [ref]

Edit the file /etc/postfix/main.cf to ensure that only the following inet_interfaces line appears:
inet_interfaces = loopback-only
        
Rationale:
This ensures postfix accepts mail messages (such as cron job reports) from the local system only, and not from the network, which protects it from network attack.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_postfix_network_listening_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
disaCCI-000382
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
anssiR74
cis2.2.15
pcidss41.4.2, 1.4

Rule   Ensure Mail Transfer Agent is not Listening on any non-loopback Address   [ref]

Mail Transfer Agents (MTA), such as sendmail and Postfix, are used to listen for incoming mail and transfer the messages to the appropriate user or mail server. If the system is not intended to be a mail server, it is recommended that the MTA be configured to only process local mail.
Rationale:
The software for all Mail Transfer Agents is complex and most have a long history of security issues. While it is important to ensure that the system can process local mail messages, it is not necessary to have the MTA's daemon listening on a port unless the server is intended to be a mail server that receives and processes mail from other systems.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_has_nonlocal_mta
References:
cis2.2.15
Group   NFS and RPC   Group contains 4 groups and 2 rules
[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   Disable All NFS Services if Possible   Group contains 1 group and 1 rule
[ref]   If there is not a reason for the system to operate as either an NFS client or an NFS server, follow all instructions in this section to disable subsystems required by NFS.
Warning:  The steps in this section will prevent a system from operating as either an NFS client or an NFS server. Only perform these steps on systems which do not need NFS at all.
Group   Disable Services Used Only by NFS   Group contains 1 rule
[ref]   If NFS is not needed, disable the NFS client daemons nfslock, rpcgssd, and rpcidmapd.

All of these daemons run with elevated privileges, and many listen for network connections. If they are not needed, they should be disabled to improve system security posture.

Rule   Disable rpcbind Service   [ref]

The rpcbind utility maps RPC services to the ports on which they listen. RPC processes notify rpcbind when they start, registering the ports they are listening on and the RPC program numbers they expect to serve. The rpcbind service redirects the client to the proper port number so it can communicate with the requested service. If the system does not require RPC (such as for NFS servers) then this service should be disabled. The rpcbind service can be disabled with the following command:
$ sudo systemctl mask --now rpcbind.service
Rationale:
If the system does not require rpc based services, it is recommended that rpcbind be disabled to reduce the attack surface.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_service_rpcbind_disabled
References:
cis2.2.17
pcidss42.2.4, 2.2


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_rpcbind_disabled

- name: Disable rpcbind 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: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_rpcbind_disabled

- name: Disable rpcbind Service - Ensure rpcbind.service is Masked
  ansible.builtin.systemd:
    name: rpcbind.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"kernel" in ansible_facts.packages'
  - service_exists.stdout_lines is search("rpcbind.service", multiline=True)
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_rpcbind_disabled

- name: Unit Socket Exists - rpcbind.socket
  ansible.builtin.command: systemctl -q list-unit-files rpcbind.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_rpcbind_disabled

- name: Disable rpcbind Service - Disable Socket rpcbind
  ansible.builtin.systemd:
    name: rpcbind.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"kernel" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("rpcbind.socket", multiline=True)
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_rpcbind_disabled

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

class disable_rpcbind {
  service {'rpcbind':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Configure NFS Clients   Group contains 1 group and 1 rule
[ref]   The steps in this section are appropriate for systems which operate as NFS clients.
Group   Disable NFS Server Daemons   Group contains 1 rule
[ref]   There is no need to run the NFS server daemons nfs and rpcsvcgssd except on a small number of properly secured systems designated as NFS servers. Ensure that these daemons are turned off on clients.

Rule   Disable Network File System (nfs)   [ref]

The Network File System (NFS) service allows remote hosts to mount and interact with shared filesystems on the local system. If the local system is not designated as a NFS server then this service should be disabled. The nfs-server service can be disabled with the following command:
$ sudo systemctl mask --now nfs-server.service
Rationale:
Unnecessary services should be disabled to decrease the attack surface of the system.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_nfs_disabled
References:
cis-csc11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.PT-3
cis2.2.16


[customizations.services]
masked = ["nfs-server"]

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nfs_disabled
  - unknown_severity

- name: Disable Network File System (nfs) - 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: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nfs_disabled
  - unknown_severity

- name: Disable Network File System (nfs) - Ensure nfs-server.service is Masked
  ansible.builtin.systemd:
    name: nfs-server.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"kernel" in ansible_facts.packages'
  - service_exists.stdout_lines is search("nfs-server.service", multiline=True)
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nfs_disabled
  - unknown_severity

- name: Unit Socket Exists - nfs-server.socket
  ansible.builtin.command: systemctl -q list-unit-files nfs-server.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nfs_disabled
  - unknown_severity

- name: Disable Network File System (nfs) - Disable Socket nfs-server
  ansible.builtin.systemd:
    name: nfs-server.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"kernel" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("nfs-server.socket", multiline=True)
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nfs_disabled
  - unknown_severity

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_nfs-server

class disable_nfs-server {
  service {'nfs-server':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Network Time Protocol   Group contains 2 rules
[ref]   The Network Time Protocol is used to manage the system clock over a network. Computer clocks are not very accurate, so time will drift unpredictably on unmanaged systems. Central time protocols can be used both to ensure that time is consistent among a network of systems, and that their time is consistent with the outside world.

If every system on a network reliably reports the same time, then it is much easier to correlate log messages in case of an attack. In addition, a number of cryptographic protocols (such as Kerberos) use timestamps to prevent certain types of attacks. If your network does not have synchronized time, these protocols may be unreliable or even unusable.

Depending on the specifics of the network, global time accuracy may be just as important as local synchronization, or not very important at all. If your network is connected to the Internet, using a public timeserver (or one provided by your enterprise) provides globally accurate timestamps which may be essential in investigating or responding to an attack which originated outside of your network.

A typical network setup involves a small number of internal systems operating as NTP servers, and the remainder obtaining time information from those internal servers.

There is a choice between the daemons ntpd and chronyd, which are available from the repositories in the ntp and chrony packages respectively.

The default chronyd daemon can work well when external time references are only intermittently accesible, can perform well even when the network is congested for longer periods of time, can usually synchronize the clock faster and with better time accuracy, and quickly adapts to sudden changes in the rate of the clock, for example, due to changes in the temperature of the crystal oscillator. Chronyd should be considered for all systems which are frequently suspended or otherwise intermittently disconnected and reconnected to a network. Mobile and virtual systems for example.

The ntpd NTP daemon fully supports NTP protocol version 4 (RFC 5905), including broadcast, multicast, manycast clients and servers, and the orphan mode. It also supports extra authentication schemes based on public-key cryptography (RFC 5906). The NTP daemon (ntpd) should be considered for systems which are normally kept permanently on. Systems which are required to use broadcast or multicast IP, or to perform authentication of packets with the Autokey protocol, should consider using ntpd.

Refer to https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/set-time.html for more detailed comparison of features of chronyd and ntpd daemon features respectively, and for further guidance how to choose between the two NTP daemons.

The upstream manual pages at https://chrony-project.org/documentation.html for chronyd and http://www.ntp.org for ntpd provide additional information on the capabilities and configuration of each of the NTP daemons.

Rule   A remote time server for Chrony is configured   [ref]

Chrony is a daemon which implements the Network Time Protocol (NTP). It is designed to synchronize system clocks across a variety of systems and use a source that is highly accurate. More information on chrony can be found at https://chrony-project.org/. Chrony can be configured to be a client and/or a server. Add or edit server or pool lines to /etc/chrony.conf as appropriate:
server <remote-server>
Multiple servers may be configured.
Rationale:
If chrony is in use on the system proper configuration is vital to ensuring time synchronization is working properly.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_chronyd_specify_remote_server
References:
disaCCI-001890, CCI-004926, CCI-004923
ism0988, 1405
nistCM-6(a), AU-8(1)(a)
pcidssReq-10.4.3
os-srgSRG-OS-000355-GPOS-00143
anssiR71
cis2.1.2
pcidss410.6.2, 10.6

# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel && { rpm --quiet -q chrony; }; then

var_multiple_time_servers='0.rhel.pool.ntp.org,1.rhel.pool.ntp.org,2.rhel.pool.ntp.org,3.rhel.pool.ntp.org'


config_file="/etc/chrony.conf"

if ! grep -q '^[[:space:]]*\(server\|pool\)[[:space:]]\+[[:graph:]]\+' "$config_file" ; then
  if ! grep -q '#[[:space:]]*server' "$config_file" ; then
    for server in $(echo "$var_multiple_time_servers" | tr ',' '\n') ; do
      printf '\nserver %s' "$server" >> "$config_file"
    done
  else
    sed -i 's/#[ \t]*server/server/g' "$config_file"
  fi
fi

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.3
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.2
  - chronyd_specify_remote_server
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
- name: XCCDF Value var_multiple_time_servers # promote to variable
  set_fact:
    var_multiple_time_servers: !!str 0.rhel.pool.ntp.org,1.rhel.pool.ntp.org,2.rhel.pool.ntp.org,3.rhel.pool.ntp.org
  tags:
    - always

- name: Detect if chrony is already configured with pools or servers
  find:
    path: /etc
    patterns: chrony.conf
    contains: ^[\s]*(?:server|pool)[\s]+[\w]+
  register: chrony_servers
  when:
  - '"kernel" in ansible_facts.packages'
  - '"chrony" in ansible_facts.packages'
  tags:
  - NIST-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.3
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.2
  - chronyd_specify_remote_server
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Configure remote time servers
  lineinfile:
    path: /etc/chrony.conf
    line: server {{ item }}
    state: present
    create: true
  loop: '{{ var_multiple_time_servers.split(",") }}'
  when:
  - '"kernel" in ansible_facts.packages'
  - '"chrony" in ansible_facts.packages'
  - chrony_servers.matched == 0
  tags:
  - NIST-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.3
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.2
  - chronyd_specify_remote_server
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Ensure that chronyd is running under chrony user account   [ref]

chrony is a daemon which implements the Network Time Protocol (NTP). It is designed to synchronize system clocks across a variety of systems and use a source that is highly accurate. More information on chrony can be found at https://chrony-project.org/. Chrony can be configured to be a client and/or a server. To ensure that chronyd is running under chrony user account, add or edit the OPTIONS variable in /etc/sysconfig/chronyd to include -u chrony:
OPTIONS="-u chrony"
This recommendation only applies if chrony is in use on the system.
Rationale:
If chrony is in use on the system proper configuration is vital to ensuring time synchronization is working properly.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_chronyd_run_as_chrony_user
References:
cis2.1.2
pcidss410.6.3, 10.6

# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel && { rpm --quiet -q chrony; }; then

if grep -q 'OPTIONS=.*' /etc/sysconfig/chronyd; then
	# trying to solve cases where the parameter after OPTIONS
	#may or may not be enclosed in quotes
	sed -i -E -e 's/\s*-u\s*\w+\s*/ /' -e 's/^([\s]*OPTIONS=["]?[^"]*)("?)/\1 -u chrony\2/' /etc/sysconfig/chronyd
else
	echo 'OPTIONS="-u chrony"' >> /etc/sysconfig/chronyd
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Obsolete Services   Group contains 3 groups and 5 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 Amazon Linux 2023 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 iptables to restrict access to the vulnerable service to only those remote hosts which have a known need to use it.
Group   Rlogin, Rsh, and Rexec   Group contains 1 rule
[ref]   The Berkeley r-commands are legacy services which allow cleartext remote access and have an insecure trust model.

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
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
Group   Telnet   Group contains 2 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 dnf remove 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
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
anssiR62
cis2.2.13
pcidss42.2.4, 2.2

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
dnf remove -y --noautoremove "telnet-server"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure telnet-server is removed
  package:
    name: telnet-server
    state: absent
  tags:
  - 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
  - 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',
  }
}

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 Amazon Linux 2023.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_telnet_removed
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
cis2.3.1
pcidss42.2.4, 2.2

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
dnf remove -y --noautoremove "telnet"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure telnet is removed
  package:
    name: telnet
    state: absent
  tags:
  - NIST-800-171-3.1.13
  - PCI-DSSv4-2.2
  - 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',
  }
}
Group   TFTP Server   Group contains 1 rule
[ref]   TFTP is a lightweight version of the FTP protocol which has traditionally been used to configure networking equipment. However, TFTP provides little security, and modern versions of networking operating systems frequently support configuration via SSH or other more secure protocols. A TFTP server should be run only if no more secure method of supporting existing equipment can be found.

Rule   Uninstall tftp-server Package   [ref]

The tftp-server package can be removed with the following command:
 $ sudo dnf remove tftp-server
Rationale:
Removing the tftp-server package decreases the risk of the accidental (or intentional) activation of tftp services.

If TFTP is required for operational support (such as transmission of router configurations), its use must be documented with the Information Systems Securty Manager (ISSM), restricted to only authorized personnel, and have access control rules established.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_tftp-server_removed
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
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
os-srgSRG-OS-000480-GPOS-00227
anssiR62
cis2.2.7
pcidss42.2.4, 2.2

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

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

if rpm -q --quiet "tftp-server" ; then
dnf remove -y --noautoremove "tftp-server"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure tftp-server is removed
  package:
    name: tftp-server
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_tftp-server_removed

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

class remove_tftp-server {
  package { 'tftp-server':
    ensure => 'purged',
  }
}

Rule   Uninstall rsync Package   [ref]

The rsyncd service can be used to synchronize files between systems over network links. The rsync package can be removed with the following command:
$ sudo dnf remove rsync
Rationale:
The rsyncd service presents a security risk as it uses unencrypted protocols for communication.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_rsync_removed
References:
cis2.2.18

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

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

if rpm -q --quiet "rsync" ; then
dnf remove -y --noautoremove "rsync"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure rsync is removed
  package:
    name: rsync
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_rsync_removed

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

class remove_rsync {
  package { 'rsync':
    ensure => 'purged',
  }
}
Group   Print Support   Group contains 1 rule
[ref]   The Common Unix Printing System (CUPS) service provides both local and network printing support. A system running the CUPS service can accept print jobs from other systems, process them, and send them to the appropriate printer. It also provides an interface for remote administration through a web browser. The CUPS service is installed and activated by default. The project homepage and more detailed documentation are available at http://www.cups.org.

Rule   Uninstall CUPS Package   [ref]

The cups package can be removed with the following command:
$ sudo dnf remove cups
Rationale:
If the system does not need to print jobs or accept print jobs from other systems, it is recommended that CUPS be removed to reduce the potential attack surface.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_cups_removed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
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-7(a), CM-7(b), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis2.2.3

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

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

if rpm -q --quiet "cups" ; then
dnf remove -y --noautoremove "cups"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure cups is removed
  package:
    name: cups
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_cups_removed
  - unknown_severity

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

class remove_cups {
  package { 'cups':
    ensure => 'purged',
  }
}
Group   Proxy Server   Group contains 1 group and 1 rule
[ref]   A proxy server is a very desirable target for a potential adversary because much (or all) sensitive data for a given infrastructure may flow through it. Therefore, if one is required, the system acting as a proxy server should be dedicated to that purpose alone and be stored in a physically secure location. The system's default proxy server software is Squid, and provided in an RPM package of the same name.
Group   Disable Squid if Possible   Group contains 1 rule
[ref]   If Squid was installed and activated, but the system does not need to act as a proxy server, then it should be disabled and removed.

Rule   Uninstall squid Package   [ref]

The squid package can be removed with the following command:
 $ sudo dnf remove squid
Rationale:
If there is no need to make the proxy server software available, removing it provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_squid_removed
References:
cis2.2.11

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

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

if rpm -q --quiet "squid" ; then
dnf remove -y --noautoremove "squid"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure squid is removed
  package:
    name: squid
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_squid_removed
  - unknown_severity

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

class remove_squid {
  package { 'squid':
    ensure => 'purged',
  }
}
Group   Samba(SMB) Microsoft Windows File Sharing Server   Group contains 1 group and 1 rule
[ref]   When properly configured, the Samba service allows Linux systems to provide file and print sharing to Microsoft Windows systems. There are two software packages that provide Samba support. The first, samba-client, provides a series of command line tools that enable a client system to access Samba shares. The second, simply labeled samba, provides the Samba service. It is this second package that allows a Linux system to act as an Active Directory server, a domain controller, or as a domain member. Only the samba-client package is installed by default.
Group   Disable Samba if Possible   Group contains 1 rule
[ref]   Even after the Samba server package has been installed, it will remain disabled. Do not enable this service unless it is absolutely necessary to provide Microsoft Windows file and print sharing functionality.

Rule   Uninstall Samba Package   [ref]

The samba package can be removed with the following command:
 $ sudo dnf remove samba
Rationale:
If there is no need to make the Samba software available, removing it provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_samba_removed
References:
cis2.2.10

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

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

if rpm -q --quiet "samba" ; then
dnf remove -y --noautoremove "samba"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure samba is removed
  package:
    name: samba
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_samba_removed
  - unknown_severity

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

class remove_samba {
  package { 'samba':
    ensure => 'purged',
  }
}
Group   SNMP Server   Group contains 1 group and 2 rules
[ref]   The Simple Network Management Protocol allows administrators to monitor the state of network devices, including computers. Older versions of SNMP were well-known for weak security, such as plaintext transmission of the community string (used for authentication) and usage of easily-guessable choices for the community string.
Group   Disable SNMP Server if Possible   Group contains 2 rules
[ref]   The system includes an SNMP daemon that allows for its remote monitoring, though it not installed by default. If it was installed and activated but is not needed, the software should be disabled and removed.

Rule   Uninstall net-snmp Package   [ref]

The net-snmp package provides the snmpd service. The net-snmp package can be removed with the following command:
$ sudo dnf remove net-snmp
Rationale:
If there is no need to run SNMP server software, removing the package provides a safeguard against its activation.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_net-snmp_removed
References:
cis2.2.12
pcidss42.2.4, 2.2

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

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

if rpm -q --quiet "net-snmp" ; then
dnf remove -y --noautoremove "net-snmp"
fi

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure net-snmp is removed
  package:
    name: net-snmp
    state: absent
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_net-snmp_removed
  - unknown_severity

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_net-snmp

class remove_net-snmp {
  package { 'net-snmp':
    ensure => 'purged',
  }
}

Rule   Disable snmpd Service   [ref]

The snmpd service can be disabled with the following command:
$ sudo systemctl mask --now snmpd.service
Rationale:
Running SNMP software provides a network-based avenue of attack, and should be disabled if not needed.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_service_snmpd_disabled
References:
ism1311
cis2.2.12


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_snmpd_disabled

- name: Disable snmpd 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: ( "net-snmp" in ansible_facts.packages and "kernel" in ansible_facts.packages
    )
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_snmpd_disabled

- name: Disable snmpd Service - Ensure snmpd.service is Masked
  ansible.builtin.systemd:
    name: snmpd.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( "net-snmp" in ansible_facts.packages and "kernel" in ansible_facts.packages
    )
  - service_exists.stdout_lines is search("snmpd.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_snmpd_disabled

- name: Unit Socket Exists - snmpd.socket
  ansible.builtin.command: systemctl -q list-unit-files snmpd.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( "net-snmp" in ansible_facts.packages and "kernel" in ansible_facts.packages
    )
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_snmpd_disabled

- name: Disable snmpd Service - Disable Socket snmpd
  ansible.builtin.systemd:
    name: snmpd.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( "net-snmp" in ansible_facts.packages and "kernel" in ansible_facts.packages
    )
  - socket_file_exists.stdout_lines is search("snmpd.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_snmpd_disabled

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

class disable_snmpd {
  service {'snmpd':
    enable => false,
    ensure => 'stopped',
  }
}
Group   SSH Server   Group contains 1 group and 24 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 15 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   [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. For SSH earlier than v8.2, a ClientAliveCountMax value of 0 causes a timeout precisely when the ClientAliveInterval is set. Starting with v8.2, a value of 0 disables the timeout functionality completely. If the option is set to a number greater than 0, then the session will be disconnected after ClientAliveInterval * ClientAliveCountMax seconds without receiving a keep alive message.
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
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-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-000163-GPOS-00072, SRG-OS-000279-GPOS-00109
cis4.2.20
pcidss48.2.8, 8.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

var_sshd_set_keepalive='1'


mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*ClientAliveCountMax\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*ClientAliveCountMax\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*ClientAliveCountMax\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "ClientAliveCountMax $var_sshd_set_keepalive" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.8
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_keepalive
- name: XCCDF Value var_sshd_set_keepalive # promote to variable
  set_fact:
    var_sshd_set_keepalive: !!str 1
  tags:
    - always

- name: Set SSH Client Alive Count Max
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "ClientAliveCountMax"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter ClientAliveCountMax is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "ClientAliveCountMax"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "ClientAliveCountMax"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "ClientAliveCountMax"| regex_escape }}\s+
      line: ClientAliveCountMax {{ var_sshd_set_keepalive }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.8
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_keepalive

Rule   Set SSH Client Alive Interval   [ref]

SSH allows administrators to set a network responsiveness timeout interval. After this interval has passed, the unresponsive client will be automatically logged out.

To set this timeout interval, edit the following line in /etc/ssh/sshd_config as follows:
ClientAliveInterval 900
        


The timeout interval is given in seconds. For example, have a timeout of 10 minutes, set interval to 600.

If a shorter timeout has already been set for the login shell, that value will preempt any SSH setting made in /etc/ssh/sshd_config. Keep in mind that some processes may stop SSH from correctly detecting that the user is idle.
Warning:  SSH disconnecting unresponsive clients will not have desired effect without also configuring ClientAliveCountMax in the SSH service configuration.
Warning:  Following conditions may prevent the SSH session to time out:
  • Remote processes on the remote machine generates output. As the output has to be transferred over the network to the client, the timeout is reset every time such transfer happens.
  • Any scp or sftp activity by the same user to the host resets the timeout.
Rationale:
Terminating an idle ssh session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been let unattended.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_idle_timeout
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-001133, CCI-002361, CCI-002891
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
nistCM-6(a), AC-17(a), AC-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, SRG-OS-000395-GPOS-00175
cis4.2.20
pcidss48.2.8, 8.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

sshd_idle_timeout_value='900'


mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*ClientAliveInterval\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*ClientAliveInterval\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*ClientAliveInterval\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "ClientAliveInterval $sshd_idle_timeout_value" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSS-Req-8.1.8
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.8
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_idle_timeout
- name: XCCDF Value sshd_idle_timeout_value # promote to variable
  set_fact:
    sshd_idle_timeout_value: !!str 900
  tags:
    - always

- name: Set SSH Client Alive Interval
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "ClientAliveInterval"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter ClientAliveInterval is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "ClientAliveInterval"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "ClientAliveInterval"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "ClientAliveInterval"| regex_escape }}\s+
      line: ClientAliveInterval {{ sshd_idle_timeout_value }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSS-Req-8.1.8
  - PCI-DSSv4-8.2
  - PCI-DSSv4-8.2.8
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_idle_timeout

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.d/00-complianceascode-hardening.conf:
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
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
cis4.2.8
pcidss48.3.1, 8.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf

LC_ALL=C sed -i "/^\s*HostbasedAuthentication\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*HostbasedAuthentication\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*HostbasedAuthentication\s\+/Id" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
else
    touch "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"

cp "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "HostbasedAuthentication no" > "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
cat "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak" >> "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-8.3.1
  - disable_host_auth
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Disable Host-Based Authentication
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "HostbasedAuthentication"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter HostbasedAuthentication is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "HostbasedAuthentication"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "HostbasedAuthentication"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "HostbasedAuthentication"| regex_escape }}\s+
      line: HostbasedAuthentication no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-8.3.1
  - disable_host_auth
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

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.d/00-complianceascode-hardening.conf:
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
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-000766, 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, 4.3.3.5.3, 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
cis4.2.9
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf

LC_ALL=C sed -i "/^\s*PermitEmptyPasswords\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*PermitEmptyPasswords\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*PermitEmptyPasswords\s\+/Id" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
else
    touch "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"

cp "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "PermitEmptyPasswords no" > "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
cat "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak" >> "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-2.2.6
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_empty_passwords

- name: Disable SSH Access via Empty Passwords
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "PermitEmptyPasswords"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter PermitEmptyPasswords is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "PermitEmptyPasswords"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "PermitEmptyPasswords"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "PermitEmptyPasswords"| regex_escape }}\s+
      line: PermitEmptyPasswords no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-2.2.6
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_empty_passwords

Rule   Disable SSH Support for .rhosts Files   [ref]

SSH can emulate the behavior of the obsolete rsh command in allowing users to enable insecure access to their accounts via .rhosts files.
The default SSH configuration disables support for .rhosts. The appropriate configuration is used if no value is set for IgnoreRhosts.
To explicitly disable support for .rhosts files, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
IgnoreRhosts yes
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_sshd_disable_rhosts
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
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
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
nistAC-17(a), CM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.IP-1, PR.PT-3
os-srgSRG-OS-000480-GPOS-00227
cis4.2.11
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf

LC_ALL=C sed -i "/^\s*IgnoreRhosts\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*IgnoreRhosts\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*IgnoreRhosts\s\+/Id" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
else
    touch "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"

cp "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "IgnoreRhosts yes" > "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
cat "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak" >> "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - 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-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_rhosts

- name: Disable SSH Support for .rhosts Files
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "IgnoreRhosts"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter IgnoreRhosts is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "IgnoreRhosts"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "IgnoreRhosts"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "IgnoreRhosts"| regex_escape }}\s+
      line: IgnoreRhosts yes
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - 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-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_disable_rhosts

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.d/00-complianceascode-hardening.conf:
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
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
cis4.2.10
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf

LC_ALL=C sed -i "/^\s*PermitUserEnvironment\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*PermitUserEnvironment\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*PermitUserEnvironment\s\+/Id" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
else
    touch "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"

cp "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf" "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "PermitUserEnvironment no" > "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
cat "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak" >> "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_do_not_permit_user_env

- name: Do Not Allow SSH Environment Options
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "PermitUserEnvironment"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter PermitUserEnvironment is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "PermitUserEnvironment"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "PermitUserEnvironment"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/01-complianceascode-reinforce-os-defaults.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "PermitUserEnvironment"| regex_escape }}\s+
      line: PermitUserEnvironment no
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - 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
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_do_not_permit_user_env

Rule   Enable PAM   [ref]

UsePAM Enables the Pluggable Authentication Module interface. If set to “yes” this will enable PAM authentication using ChallengeResponseAuthentication and PasswordAuthentication in addition to PAM account and session module processing for all authentication types. To enable PAM authentication, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
UsePAM yes
Rationale:
When UsePAM is set to yes, PAM runs through account and session types properly. This is important if you want to restrict access to services based off of IP, time or other factors of the account. Additionally, you can make sure users inherit certain environment variables on login or disallow access to the server.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_enable_pam
References:
disaCCI-000877
os-srgSRG-OS-000125-GPOS-00065
cis4.2.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*UsePAM\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*UsePAM\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*UsePAM\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "UsePAM yes" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_enable_pam

- name: Enable PAM
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "UsePAM"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter UsePAM is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "UsePAM"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "UsePAM"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "UsePAM"| regex_escape }}\s+
      line: UsePAM yes
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_enable_pam

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.net
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_net
References:
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
os-srgSRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088
cis4.2.15

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Banner\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "Banner /etc/issue.net" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.6
  - 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)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_enable_warning_banner_net

- name: Enable SSH Warning Banner
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "Banner"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter Banner is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "Banner"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "Banner"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "Banner"| regex_escape }}\s+
      line: Banner /etc/issue.net
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - CJIS-5.5.6
  - 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)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_enable_warning_banner_net

Rule   Limit Users' SSH Access   [ref]

By default, the SSH configuration allows any user with an account to access the system. There are several options available to limit which users and group can access the system via SSH. It is recommended that at least one of the following options be leveraged: - AllowUsers variable gives the system administrator the option of allowing specific users to ssh into the system. The list consists of space separated user names. Numeric user IDs are not recognized with this variable. If a system administrator wants to restrict user access further by specifically allowing a user's access only from a particular host, the entry can be specified in the form of user@host. - AllowGroups variable gives the system administrator the option of allowing specific groups of users to ssh into the system. The list consists of space separated group names. Numeric group IDs are not recognized with this variable. - DenyUsers variable gives the system administrator the option of denying specific users to ssh into the system. The list consists of space separated user names. Numeric user IDs are not recognized with this variable. If a system administrator wants to restrict user access further by specifically denying a user's access from a particular host, the entry can be specified in the form of user@host. - DenyGroups variable gives the system administrator the option of denying specific groups of users to ssh into the system. The list consists of space separated group names. Numeric group IDs are not recognized with this variable.
Warning:  Automated remediation is not available for this configuration check because each system has unique user names and group names.
Rationale:
Specifying which accounts are allowed SSH access into the system reduces the possibility of unauthorized access to the system.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_sshd_limit_user_access
References:
cis-csc11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06
cui3.1.12
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
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, CM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.PT-3
pcidssReq-2.2.4
cis4.2.4
pcidss42.2.6, 2.2

Rule   Set SSH Daemon LogLevel to VERBOSE   [ref]

The VERBOSE parameter configures the SSH daemon to record login and logout activity. To specify the log level in SSH, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
LogLevel VERBOSE
Rationale:
SSH provides several logging levels with varying amounts of verbosity. DEBUG is specifically not recommended other than strictly for debugging SSH communications since it provides so much data that it is difficult to identify important security information. INFO or VERBOSE level is the basic level that only records login activity of SSH users. In many situations, such as Incident Response, it is important to determine when a particular user was active on a system. The logout record can eliminate those users who disconnected, which helps narrow the field.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_loglevel_verbose
References:
disaCCI-000067
nerc-cipCIP-007-3 R7.1
nistAC-17(a), AC-17(1), CM-6(a)
pcidssReq-2.2.4
os-srgSRG-OS-000032-GPOS-00013
cis4.2.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*LogLevel\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*LogLevel\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*LogLevel\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "LogLevel VERBOSE" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_loglevel_verbose

- name: Set SSH Daemon LogLevel to VERBOSE
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "LogLevel"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter LogLevel is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "LogLevel"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "LogLevel"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "LogLevel"| regex_escape }}\s+
      line: LogLevel VERBOSE
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-17(1)
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_loglevel_verbose

Rule   Set SSH authentication attempt limit   [ref]

The MaxAuthTries parameter specifies the maximum number of authentication attempts permitted per connection. Once the number of failures reaches half this value, additional failures are logged. to set MaxAUthTries edit /etc/ssh/sshd_config as follows:
MaxAuthTries 4
        
Rationale:
Setting the MaxAuthTries parameter to a low number will minimize the risk of successful brute force attacks to the SSH server.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_max_auth_tries
References:
ism0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561
cis4.2.16
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

sshd_max_auth_tries_value='4'


mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*MaxAuthTries\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*MaxAuthTries\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*MaxAuthTries\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "MaxAuthTries $sshd_max_auth_tries_value" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_max_auth_tries
- name: XCCDF Value sshd_max_auth_tries_value # promote to variable
  set_fact:
    sshd_max_auth_tries_value: !!str 4
  tags:
    - always

- name: Set SSH authentication attempt limit
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "MaxAuthTries"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter MaxAuthTries is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "MaxAuthTries"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "MaxAuthTries"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "MaxAuthTries"| regex_escape }}\s+
      line: MaxAuthTries {{ sshd_max_auth_tries_value }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_max_auth_tries

Rule   Set SSH MaxSessions limit   [ref]

The MaxSessions parameter specifies the maximum number of open sessions permitted from a given connection. To set MaxSessions edit /etc/ssh/sshd_config as follows:
MaxSessions 10
        
Rationale:
To protect a system from denial of service due to a large number of concurrent sessions, use the rate limiting function of MaxSessions to protect availability of sshd logins and prevent overwhelming the daemon.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_max_sessions
References:
cis4.2.18
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

var_sshd_max_sessions='10'


mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*MaxSessions\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*MaxSessions\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*MaxSessions\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "MaxSessions $var_sshd_max_sessions" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_max_sessions
- name: XCCDF Value var_sshd_max_sessions # promote to variable
  set_fact:
    var_sshd_max_sessions: !!str 10
  tags:
    - always

- name: Set SSH MaxSessions limit
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "MaxSessions"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter MaxSessions is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "MaxSessions"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "MaxSessions"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "MaxSessions"| regex_escape }}\s+
      line: MaxSessions {{ var_sshd_max_sessions }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_max_sessions

Rule   Ensure SSH MaxStartups is configured   [ref]

The MaxStartups parameter specifies the maximum number of concurrent unauthenticated connections to the SSH daemon. Additional connections will be dropped until authentication succeeds or the LoginGraceTime expires for a connection. To configure MaxStartups, you should add or edit the following line in the /etc/ssh/sshd_config file:
MaxStartups 10:30:60
        
Rationale:
To protect a system from denial of service due to a large number of pending authentication connection attempts, use the rate limiting function of MaxStartups to protect availability of sshd logins and prevent overwhelming the daemon.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_maxstartups
References:
cis4.2.17
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

var_sshd_set_maxstartups='10:30:60'


mkdir -p /etc/ssh/sshd_config.d
touch /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf

LC_ALL=C sed -i "/^\s*MaxStartups\s\+/Id" "/etc/ssh/sshd_config"
LC_ALL=C sed -i "/^\s*MaxStartups\s\+/Id" "/etc/ssh/sshd_config.d"/*.conf
if [ -e "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*MaxStartups\s\+/Id" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
else
    touch "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"

cp "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf" "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"
# Insert at the beginning of the file
printf '%s\n' "MaxStartups $var_sshd_set_maxstartups" > "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
cat "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak" >> "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.d/00-complianceascode-hardening.conf.bak"

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_maxstartups
- name: XCCDF Value var_sshd_set_maxstartups # promote to variable
  set_fact:
    var_sshd_set_maxstartups: !!str 10:30:60
  tags:
    - always

- name: Ensure SSH MaxStartups is configured
  block:

  - name: Deduplicate values from /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: false
      regexp: (?i)(?i)^\s*{{ "MaxStartups"| regex_escape }}\s+
      state: absent

  - name: Check if /etc/ssh/sshd_config.d exists
    stat:
      path: /etc/ssh/sshd_config.d
    register: _etc_ssh_sshd_config_d_exists

  - name: Check if the parameter MaxStartups is present in /etc/ssh/sshd_config.d
    find:
      paths: /etc/ssh/sshd_config.d
      recurse: 'yes'
      follow: 'no'
      contains: (?i)^\s*{{ "MaxStartups"| regex_escape }}\s+
    register: _etc_ssh_sshd_config_d_has_parameter
    when: _etc_ssh_sshd_config_d_exists.stat.isdir is defined and _etc_ssh_sshd_config_d_exists.stat.isdir

  - name: Remove parameter from files in /etc/ssh/sshd_config.d
    lineinfile:
      path: '{{ item.path }}'
      create: false
      regexp: (?i)(?i)^\s*{{ "MaxStartups"| regex_escape }}\s+
      state: absent
    with_items: '{{ _etc_ssh_sshd_config_d_has_parameter.files }}'
    when: _etc_ssh_sshd_config_d_has_parameter.matched

  - name: Insert correct line to /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
    lineinfile:
      path: /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf
      create: true
      regexp: (?i)(?i)^\s*{{ "MaxStartups"| regex_escape }}\s+
      line: MaxStartups {{ var_sshd_set_maxstartups }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"kernel" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_maxstartups

Rule   Verify Group Who Owns SSH Server config file   [ref]

To properly set the group owner of /etc/ssh/sshd_config, run the command:
$ sudo chgrp root /etc/ssh/sshd_config
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_sshd_config
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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-17(a), CM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chgrp 0 /etc/ssh/sshd_config

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_groupowner_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/ssh/sshd_config
  stat:
    path: /etc/ssh/sshd_config
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_groupowner_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/ssh/sshd_config
  file:
    path: /etc/ssh/sshd_config
    group: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_groupowner_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Ownership on SSH Server Private *_key Key Files   [ref]

SSH server private keys, files that match the /etc/ssh/*_key glob, must be group-owned by ssh_keys group.
Warning:  Remediation is not possible at bootable container build time because SSH host keys are generated post-deployment.
Rationale:
If an unauthorized user obtains the private SSH host key file, the host could be impersonated.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupownership_sshd_private_key
References:
anssiR50
cis4.2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -L /etc/ssh/ -maxdepth 1 -type f ! -group ssh_keys -regextype posix-extended -regex '^.*_key$' -exec chgrp -L ssh_keys {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - file_groupownership_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/ssh/ file(s) matching ^.*_key$
  command: find -H /etc/ssh/ -maxdepth 1 -type f ! -group ssh_keys -regextype posix-extended
    -regex "^.*_key$"
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_groupownership_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/ssh/ file(s) matching ^.*_key$
  file:
    path: '{{ item }}'
    group: ssh_keys
    state: file
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_groupownership_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Group Ownership on SSH Server Public *.pub Key Files   [ref]

SSH server public keys, files that match the /etc/ssh/*.pub glob, must be group-owned by root group.
Warning:  Remediation is not possible at bootable container build time because SSH host keys are generated post-deployment.
Rationale:
If a public host key file is modified by an unauthorized user, the SSH service may be compromised.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupownership_sshd_pub_key
References:
anssiR50
cis4.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -L /etc/ssh/ -maxdepth 1 -type f ! -group 0 -regextype posix-extended -regex '^.*\.pub$' -exec chgrp -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - file_groupownership_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/ssh/ file(s) matching ^.*\.pub$
  command: find -H /etc/ssh/ -maxdepth 1 -type f ! -group 0 -regextype posix-extended
    -regex "^.*\.pub$"
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_groupownership_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner on /etc/ssh/ file(s) matching ^.*\.pub$
  file:
    path: '{{ item }}'
    group: '0'
    state: file
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_groupownership_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Owner on SSH Server config file   [ref]

To properly set the owner of /etc/ssh/sshd_config, run the command:
$ sudo chown root /etc/ssh/sshd_config 
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_sshd_config
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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-17(a), CM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chown 0 /etc/ssh/sshd_config

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_owner_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/ssh/sshd_config
  stat:
    path: /etc/ssh/sshd_config
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_owner_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/ssh/sshd_config
  file:
    path: /etc/ssh/sshd_config
    owner: '0'
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_owner_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Ownership on SSH Server Private *_key Key Files   [ref]

SSH server private keys, files that match the /etc/ssh/*_key glob, must be owned by root user.
Warning:  Remediation is not possible at bootable container build time because SSH host keys are generated post-deployment.
Rationale:
If an unauthorized user obtains the private SSH host key file, the host could be impersonated.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_ownership_sshd_private_key
References:
anssiR50
cis4.2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -L /etc/ssh/ -maxdepth 1 -type f ! -uid 0 -regextype posix-extended -regex '^.*_key$' -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - file_ownership_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/ssh/ file(s) matching ^.*_key$
  command: find -H /etc/ssh/ -maxdepth 1 -type f ! -uid 0 -regextype posix-extended
    -regex "^.*_key$"
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_ownership_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on /etc/ssh/ file(s) matching ^.*_key$
  file:
    path: '{{ item }}'
    owner: '0'
    state: file
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_ownership_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Ownership on SSH Server Public *.pub Key Files   [ref]

SSH server public keys, files that match the /etc/ssh/*.pub glob, must be owned by root user.
Warning:  Remediation is not possible at bootable container build time because SSH host keys are generated post-deployment.
Rationale:
If a public host key file is modified by an unauthorized user, the SSH service may be compromised.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_ownership_sshd_pub_key
References:
anssiR50
cis4.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -L /etc/ssh/ -maxdepth 1 -type f ! -uid 0 -regextype posix-extended -regex '^.*\.pub$' -exec chown -L 0 {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - configure_strategy
  - file_ownership_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/ssh/ file(s) matching ^.*\.pub$
  command: find -H /etc/ssh/ -maxdepth 1 -type f ! -uid 0 -regextype posix-extended
    -regex "^.*\.pub$"
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_ownership_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner on /etc/ssh/ file(s) matching ^.*\.pub$
  file:
    path: '{{ item }}'
    owner: '0'
    state: file
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_ownership_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on SSH Server config file   [ref]

To properly set the permissions of /etc/ssh/sshd_config, run the command:
$ sudo chmod 0600 /etc/ssh/sshd_config
Rationale:
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations. Therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_sshd_config
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
disaCCI-000366
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-17(a), CM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis4.2.1
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

chmod u-xs,g-xwrs,o-xwrt /etc/ssh/sshd_config

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/ssh/sshd_config
  stat:
    path: /etc/ssh/sshd_config
  register: file_exists
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /etc/ssh/sshd_config
  file:
    path: /etc/ssh/sshd_config
    mode: u-xs,g-xwrs,o-xwrt
  when:
  - '"kernel" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_config
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on SSH Server Private *_key Key Files   [ref]

SSH server private keys - files that match the /etc/ssh/*_key glob, have to have restricted permissions. If those files are owned by the root user and the root group, they have to have the 0600 permission or stricter. If they are owned by the root user, but by a dedicated group ssh_keys, they can have the 0640 permission or stricter.
Warning:  Remediation is not possible at bootable container build time because SSH host keys are generated post-deployment.
Rationale:
If an unauthorized user obtains the private SSH host key file, the host could be impersonated.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_sshd_private_key
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.1.13, 3.13.10
disaCCI-000366
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-17(a), CM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
pcidssReq-2.2.4
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis4.2.2
pcidss42.2.6, 2.2

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

for keyfile in /etc/ssh/*_key; do
    test -f "$keyfile" || continue
    if test root:root = "$(stat -c "%U:%G" "$keyfile")"; then
    
	chmod u-xs,g-xwrs,o-xwrt "$keyfile"
    
    elif test root:ssh_keys = "$(stat -c "%U:%G" "$keyfile")"; then
	chmod u-xs,g-xws,o-xwrt "$keyfile"
    else
        echo "Key-like file '$keyfile' is owned by an unexpected user:group combination"
    fi
done

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find root:root-owned keys
  ansible.builtin.command: find -H /etc/ssh/ -maxdepth 1 -user root -regex ".*_key$"
    -type f -group root -perm /u+xs,g+xwrs,o+xwrt
  register: root_owned_keys
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for root:root-owned keys
  ansible.builtin.file:
    path: '{{ item }}'
    mode: u-xs,g-xwrs,o-xwrt
    state: file
  with_items:
  - '{{ root_owned_keys.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find root:ssh_keys-owned keys
  ansible.builtin.command: find -H /etc/ssh/ -maxdepth 1 -user root -regex ".*_key$"
    -type f -group ssh_keys -perm /u+xs,g+xws,o+xwrt
  register: dedicated_group_owned_keys
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for root:ssh_keys-owned keys
  ansible.builtin.file:
    path: '{{ item }}'
    mode: u-xs,g-xws,o-xwrt
    state: file
  with_items:
  - '{{ dedicated_group_owned_keys.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_private_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

include ssh_private_key_perms

class ssh_private_key_perms {
  exec { 'sshd_priv_key':
    command => "chmod 0640 /etc/ssh/*_key",
    path    => '/bin:/usr/bin'
  }
}

Rule   Verify Permissions on SSH Server Public *.pub Key Files   [ref]

To properly set the permissions of /etc/ssh/*.pub, run the command:
$ sudo chmod 0644 /etc/ssh/*.pub
Warning:  Remediation is not possible at bootable container build time because SSH host keys are generated post-deployment.
Rationale:
If a public host key file is modified by an unauthorized user, the SSH service may be compromised.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_sshd_pub_key
References:
cis-csc12, 13, 14, 15, 16, 18, 3, 5
cobit5APO01.06, DSS05.04, DSS05.07, DSS06.02
cui3.1.13, 3.13.10
disaCCI-000366
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-17(a), CM-6(a), AC-6(1)
nist-csfPR.AC-4, PR.DS-5
pcidssReq-2.2.4
os-srgSRG-OS-000480-GPOS-00227
anssiR50
cis4.2.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if rpm --quiet -q kernel; then

find -L /etc/ssh/ -maxdepth 1 -perm /u+xs,g+xws,o+xwt  -type f -regextype posix-extended -regex '^.*\.pub$' -exec chmod u-xs,g-xws,o-xwt {} \;

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Find /etc/ssh/ file(s)
  command: find -H /etc/ssh/ -maxdepth 1 -perm /u+xs,g+xws,o+xwt  -type f -regextype
    posix-extended -regex "^.*\.pub$"
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/ssh/ file(s)
  file:
    path: '{{ item }}'
    mode: u-xs,g-xws,o-xwt
    state: file
  with_items:
  - '{{ files_found.stdout_lines }}'
  when: '"kernel" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.13
  - NIST-800-171-3.13.10
  - NIST-800-53-AC-17(a)
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-2.2.4
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - configure_strategy
  - file_permissions_sshd_pub_key
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

include ssh_public_key_perms

class ssh_public_key_perms {
  exec { 'sshd_pub_key':
    command => "chmod 0644 /etc/ssh/*.pub",
    path    => '/bin:/usr/bin'
  }
}
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