Guide to the Secure Configuration of Ubuntu 24.04

with profile DRAFT - CIS Ubuntu Linux 24.04 LTS Benchmark for Level 1 - Server
This profile defines a baseline that aligns to the "Level 1 - Server" configuration from the Center for Internet Security® Ubuntu Linux 24.04 LTS Benchmark™, v1.0.0, released 2024-08-26. This profile includes Center for Internet Security® Ubuntu Linux 24.04 LTS Benchmark™ content.
This guide presents a catalog of security-relevant configuration settings for Ubuntu 24.04. 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 TitleDRAFT - CIS Ubuntu Linux 24.04 LTS Benchmark for Level 1 - Server
Profile IDxccdf_org.ssgproject.content_profile_cis_level1_server

CPE Platforms

  • cpe:/o:canonical:ubuntu_linux:24.04::~~lts~~~

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. AppArmor
    4. GRUB2 bootloader configuration
    5. Configure Syslog
    6. Network Configuration and Firewalls
    7. File Permissions and Masks
  2. Services
    1. Apport Service
    2. Avahi Server
    3. Cron and At Daemons
    4. Deprecated services
    5. DHCP
    6. DNS Server
    7. FTP Server
    8. Web Server
    9. IMAP and POP3 Server
    10. LDAP
    11. NFS and RPC
    12. Network Time Protocol
    13. Obsolete Services
    14. Print Support
    15. Proxy Server
    16. Samba(SMB) Microsoft Windows File Sharing Server
    17. SNMP Server
    18. SSH Server

Checklist

Group   Guide to the Secure Configuration of Ubuntu 24.04   Group contains 95 groups and 320 rules
Group   System Settings   Group contains 53 groups and 215 rules
[ref]   Contains rules that check correct system settings.
Group   Installing and Maintaining Software   Group contains 9 groups and 19 rules
[ref]   The following sections contain information on security-relevant choices during the initial operating system installation process and the setup of software updates.
Group   System and Software Integrity   Group contains 2 groups and 4 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 3 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 3 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:
$ apt-get 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
cis6.3.1
pcidss411.5.2

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "aide"

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


[[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: '"linux-base" 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 aideinit
By default, the database will be written to the file /var/lib/aide/aide.db.new. Storing the database, the configuration file /etc/aide.conf, and the binary /usr/bin/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 /var/lib/aide/aide.db
To initiate a manual check, run the following command:
$ sudo /usr/bin/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
cis6.3.1
pcidss411.5.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "aide"

AIDE_CONFIG=/etc/aide/aide.conf
DEFAULT_DB_PATH=/var/lib/aide/aide.db

# Fix db path in the config file, if necessary
if ! grep -q '^database=file:' ${AIDE_CONFIG}; then
    # replace_or_append gets confused by 'database=file' as a key, so should not be used.
    #replace_or_append "${AIDE_CONFIG}" '^database=file' "${DEFAULT_DB_PATH}" '@CCENUM@' '%s:%s'
    echo "database=file:${DEFAULT_DB_PATH}" >> ${AIDE_CONFIG}
fi

# Fix db out path in the config file, if necessary
if ! grep -q '^database_out=file:' ${AIDE_CONFIG}; then
    echo "database_out=file:${DEFAULT_DB_PATH}.new" >> ${AIDE_CONFIG}
fi

/usr/sbin/aideinit -y -f

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-5.10.1.3
  - 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.apt:
    name: aide
    state: present
  when: '"linux-base" 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 if DB Path in /etc/aide/aide.conf Is
    Already Set
  ansible.builtin.lineinfile:
    path: /etc/aide/aide.conf
    regexp: ^#?(\s*)(database=)(.*)$
    state: absent
  check_mode: true
  changed_when: false
  register: database_replace
  when: '"linux-base" 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 if DB Out Path in /etc/aide/aide.conf
    Is Already Set
  ansible.builtin.lineinfile:
    path: /etc/aide/aide.conf
    regexp: ^#?(\s*)(database_out=)(.*)$
    state: absent
  check_mode: true
  changed_when: false
  register: database_out_replace
  when: '"linux-base" 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 - Fix DB Path in Config File if Necessary
  ansible.builtin.lineinfile:
    path: /etc/aide/aide.conf
    regexp: ^#?(\s*)(database)(\s*)=(\s*)(.*)$
    line: \2\3=\4file:/var/lib/aide/aide.db
    backrefs: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - database_replace.found > 0
  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 - Fix DB Out Path in Config File if Necessary
  ansible.builtin.lineinfile:
    path: /etc/aide/aide.conf
    regexp: ^#?(\s*)(database_out)(\s*)=(\s*)(.*)$
    line: \2\3=\4file:/var/lib/aide/aide.db.new
    backrefs: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - database_out_replace.found > 0
  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 the Default DB Path is Added
  ansible.builtin.lineinfile:
    path: /etc/aide/aide.conf
    line: database=file:/var/lib/aide/aide.db
    create: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - database_replace.found == 0
  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 the Default Out Path is Added
  ansible.builtin.lineinfile:
    path: /etc/aide/aide.conf
    line: database_out=file:/var/lib/aide/aide.db.new
    create: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - database_out_replace.found == 0
  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/aideinit -y -f
  when: '"linux-base" 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

Rule   Configure Systemd Timer Execution of AIDE   [ref]

At a minimum, AIDE should be configured to run a weekly scan. To implement a systemd service and a timer unit to run the service periodically: For example, if a systemd timer is expected to be started every day at 5AM
OnCalendar=*-*-* 05:00:0
[Timer]
section in the timer unit and a Unit section starting the AIDE check service unit should be referred.
Rationale:
AIDE provides a means to check if unauthorized changes are made to the system. AIDE itself does not setup a periodic execution, so in order to detect unauthorized changes a systemd service to run the check and a systemd timer to take care of periodical execution of that systemd service should be defined.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_aide_periodic_checking_systemd_timer
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-001744, CCI-002699, CCI-002702
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
cis6.3.2
pcidss411.5.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { ( dpkg-query --show --showformat='${db:Status-Status}\n' 'aide' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}\n' 'systemd' 2>/dev/null | grep -q installed ); }; then

#!/bin/bash

DEBIAN_FRONTEND=noninteractive apt-get install -y "aide"

systemctl unmask dailyaidecheck.service
systemctl unmask dailyaidecheck.timer
systemctl --now enable dailyaidecheck.timer

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-5.10.1.3
  - 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_checking_systemd_timer
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Configure Systemd Timer Execution of AIDE - Ensure AIDE Service is Enabled
  ansible.builtin.systemd:
    name: dailyaidecheck.service
    enabled: true
    daemon_reload: true
    masked: false
  when:
  - '"linux-base" in ansible_facts.packages'
  - ( "aide" in ansible_facts.packages and "systemd" 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_checking_systemd_timer
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Configure Systemd Timer Execution of AIDE - Ensure AIDE Service Timer is Enabled
  ansible.builtin.systemd:
    name: dailyaidecheck.timer
    state: started
    enabled: true
    daemon_reload: true
    masked: false
  when:
  - '"linux-base" in ansible_facts.packages'
  - ( "aide" in ansible_facts.packages and "systemd" 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_checking_systemd_timer
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
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:
cis1.1.2.2.1

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
cis1.1.2.1.1
Group   GNOME Desktop Environment   Group contains 3 groups and 8 rules
[ref]   GNOME is a graphical desktop environment bundled with many Linux distributions that allow users to easily interact with the operating system graphically rather than textually. The GNOME Graphical Display Manager (GDM) provides login, logout, and user switching contexts as well as display server management.

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

For more information on GNOME and the GNOME Project, see https://www.gnome.org.
Group   Configure GNOME Login Screen   Group contains 2 rules

Rule   Disable the GNOME3 Login User List   [ref]

In the default graphical environment, users logging directly into the system are greeted with a login screen that displays all known users. This functionality should be disabled by setting disable-user-list to true.

To disable, add or edit disable-user-list to /etc/dconf/db/gdm.d/00-security-settings. For example:
[org/gnome/login-screen]
disable-user-list=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/disable-user-list
After the settings have been set, run dconf update.
Rationale:
Leaving the user list enabled is a security risk since it allows anyone with physical access to the system to quickly enumerate known user accounts without logging in.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_disable_user_list
References:
disaCCI-000366
nistCM-6(a), AC-23
os-srgSRG-OS-000480-GPOS-00227
cis1.7.3

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)


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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*disable-user-list\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*disable-user-list\\s*=\\s*.*/disable-user-list=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/login-screen\\]|a\\disable-user-list=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/login-screen/disable-user-list$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|gdm.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/gdm.d/locks"

mkdir -p "${LOCKSFOLDER}"

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

if ! grep -qr "^/org/gnome/login-screen/disable-user-list$" /etc/dconf/db/gdm.d/
then
    echo "/org/gnome/login-screen/disable-user-list" >> "/etc/dconf/db/gdm.d/locks/00-security-settings-lock"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

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

Rule   Disable XDMCP in GDM   [ref]

XDMCP is an unencrypted protocol, and therefore, presents a security risk, see e.g. XDMCP Gnome docs. To disable XDMCP support in Gnome, set Enable to false under the [xdmcp] configuration section in /etc/gdm/custom.conf. For example:
[xdmcp]
Enable=false
Rationale:
XDMCP provides unencrypted remote access through the Gnome Display Manager (GDM) which does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to login using XDMCP, the privileged user password could be compromised due to typed XEvents and keystrokes will traversing over the network in clear text.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_gnome_gdm_disable_xdmcp
References:
cis1.7.10

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed; then

# Try find '[xdmcp]' and 'Enable' in '/etc/gdm3/custom.conf', if it exists, set
# to 'false', if it isn't here, add it, if '[xdmcp]' doesn't exist, add it there
if grep -qzosP '[[:space:]]*\[xdmcp]([^\n\[]*\n+)+?[[:space:]]*Enable' '/etc/gdm3/custom.conf'; then
    
    sed -i "s/Enable[^(\n)]*/Enable=false/" '/etc/gdm3/custom.conf'
elif grep -qs '[[:space:]]*\[xdmcp]' '/etc/gdm3/custom.conf'; then
    sed -i "/[[:space:]]*\[xdmcp]/a Enable=false" '/etc/gdm3/custom.conf'
else
    if test -d "/etc/gdm3"; then
        printf '%s\n' '[xdmcp]' "Enable=false" >> '/etc/gdm3/custom.conf'
    else
        echo "Config file directory '/etc/gdm3' doesnt exist, not remediating, assuming non-applicability." >&2
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   GNOME Media Settings   Group contains 3 rules
[ref]   GNOME media settings that apply to the graphical interface.

Rule   Disable GNOME3 Automounting   [ref]

The system's default desktop environment, GNOME3, will mount devices and removable media (such as DVDs, CDs and USB flash drives) whenever they are inserted into the system. To disable automount within GNOME3, add or set automount to false in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/media-handling]
automount=false
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/media-handling/automount
After the settings have been set, run dconf update.
Rationale:
Disabling automatic mounting in GNOME3 can prevent the introduction of malware via removable media. It will, however, also prevent desktop users from legitimate use of removable media.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_disable_automount
References:
cis-csc12, 16
cobit5APO13.01, DSS01.04, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03
cui3.1.7
disaCCI-000366, CCI-000778, CCI-001958
isa-62443-20094.3.3.2.2, 4.3.3.5.2, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.4, SR 1.5, SR 1.9, SR 2.1, SR 2.6
iso27001-2013A.11.2.6, A.13.1.1, A.13.2.1, A.6.2.1, A.6.2.2, A.7.1.1, A.9.2.1
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.AC-6
os-srgSRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227
cis1.7.6, 1.7.7
pcidss43.4.2, 3.4

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)


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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "false")"
if grep -q "^\\s*automount\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*automount\\s*=\\s*.*/automount=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/desktop/media-handling\\]|a\\automount=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/desktop/media-handling/automount$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|local.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/local.d/locks"

mkdir -p "${LOCKSFOLDER}"

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

if ! grep -qr "^/org/gnome/desktop/media-handling/automount$" /etc/dconf/db/local.d/
then
    echo "/org/gnome/desktop/media-handling/automount" >> "/etc/dconf/db/local.d/locks/00-security-settings-lock"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

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

Rule   Disable GNOME3 Automount Opening   [ref]

The system's default desktop environment, GNOME3, will mount devices and removable media (such as DVDs, CDs and USB flash drives) whenever they are inserted into the system. To disable automount-open within GNOME3, add or set automount-open to false in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/media-handling]
automount-open=false
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/media-handling/automount-open
After the settings have been set, run dconf update.
Rationale:
Automatically mounting file systems permits easy introduction of unknown devices, thereby facilitating malicious activity. Disabling automatic mounting in GNOME3 can prevent the introduction of malware via removable media. It will, however, also prevent desktop users from legitimate use of removable media.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_disable_automount_open
References:
cis-csc12, 16
cobit5APO13.01, DSS01.04, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03
cui3.1.7
disaCCI-000778, CCI-000366, CCI-001958
isa-62443-20094.3.3.2.2, 4.3.3.5.2, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.4, SR 1.5, SR 1.9, SR 2.1, SR 2.6
iso27001-2013A.11.2.6, A.13.1.1, A.13.2.1, A.6.2.1, A.6.2.2, A.7.1.1, A.9.2.1
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.AC-6
os-srgSRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227
cis1.7.6, 1.7.7
pcidss43.4.2, 3.4

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)


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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "false")"
if grep -q "^\\s*automount-open\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*automount-open\\s*=\\s*.*/automount-open=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/desktop/media-handling\\]|a\\automount-open=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/desktop/media-handling/automount-open$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|local.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/local.d/locks"

mkdir -p "${LOCKSFOLDER}"

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

if ! grep -qr "^/org/gnome/desktop/media-handling/automount-open$" /etc/dconf/db/local.d/
then
    echo "/org/gnome/desktop/media-handling/automount-open" >> "/etc/dconf/db/local.d/locks/00-security-settings-lock"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

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

Rule   Disable GNOME3 Automount running   [ref]

The system's default desktop environment, GNOME3, will mount devices and removable media (such as DVDs, CDs and USB flash drives) whenever they are inserted into the system. To disable autorun-never within GNOME3, add or set autorun-never to true in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/media-handling]
autorun-never=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/media-handling/autorun-never
After the settings have been set, run dconf update.
Rationale:
Automatically mounting file systems permits easy introduction of unknown devices, thereby facilitating malicious activity. Disabling automatic mount running in GNOME3 can prevent the introduction of malware via removable media. It will, however, also prevent desktop users from legitimate use of removable media.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_disable_autorun
References:
cis-csc12, 16
cobit5APO13.01, DSS01.04, DSS05.03, DSS05.04, DSS05.05, DSS05.07, DSS06.03
cui3.1.7
disaCCI-000366, CCI-001764, CCI-001958, CCI-000778
isa-62443-20094.3.3.2.2, 4.3.3.5.2, 4.3.3.6.6, 4.3.3.7.2, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.13, SR 1.2, SR 1.4, SR 1.5, SR 1.9, SR 2.1, SR 2.6
iso27001-2013A.11.2.6, A.13.1.1, A.13.2.1, A.6.2.1, A.6.2.2, A.7.1.1, A.9.2.1
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.AC-6
os-srgSRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227
cis1.7.8, 1.7.9

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)


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

mkdir -p "${DBDIR}"

# Comment out the configurations in databases different from the target one
if [ "${#SETTINGSFILES[@]}" -ne 0 ]
then
    if grep -q "^\\s*autorun-never\\s*=" "${SETTINGSFILES[@]}"
    then
        
        sed -Ei "s/(^\s*)autorun-never(\s*=)/#\1autorun-never\2/g" "${SETTINGSFILES[@]}"
    fi
fi

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*autorun-never\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*autorun-never\\s*=\\s*.*/autorun-never=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/desktop/media-handling\\]|a\\autorun-never=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/desktop/media-handling/autorun-never$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|local.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/local.d/locks"

mkdir -p "${LOCKSFOLDER}"

# Comment out the configurations in databases different from the target one
if [[ ! -z "${LOCKFILES}" ]]
then
    sed -i -E "s|^/org/gnome/desktop/media-handling/autorun-never$|#&|" "${LOCKFILES[@]}"
fi

if ! grep -qr "^/org/gnome/desktop/media-handling/autorun-never$" /etc/dconf/db/local.d/
then
    echo "/org/gnome/desktop/media-handling/autorun-never" >> "/etc/dconf/db/local.d/locks/00-security-settings-lock"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Configure GNOME Screen Locking   Group contains 3 rules
[ref]   In the default GNOME3 desktop, the screen can be locked by selecting the user name in the far right corner of the main panel and selecting Lock.

The following sections detail commands to enforce idle activation of the screensaver, screen locking, a blank-screen screensaver, and an idle activation time.

Because users should be trained to lock the screen when they step away from the computer, the automatic locking feature is only meant as a backup.

The root account can be screen-locked; however, the root account should never be used to log into an X Windows environment and should only be used to for direct login via console in emergency circumstances.

For more information about enforcing preferences in the GNOME3 environment using the DConf configuration system, see http://wiki.gnome.org/dconf and the man page dconf(1).

Rule   Set GNOME3 Screensaver Inactivity Timeout   [ref]

The idle time-out value for inactivity in the GNOME3 desktop is configured via the idle-delay setting must be set under an appropriate configuration file(s) in the /etc/dconf/db/local.d directory and locked in /etc/dconf/db/local.d/locks directory to prevent user modification.

For example, to configure the system for a 15 minute delay, add the following to /etc/dconf/db/local.d/00-security-settings:
[org/gnome/desktop/session]
idle-delay=uint32 900
Rationale:
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME3 can be configured to identify when a user's session has idled and take action to initiate a session lock.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_delay
References:
cis-csc1, 12, 15, 16
cjis5.5.5
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.10
disaCCI-000057, CCI-000060
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-11(a), CM-6(a)
nist-csfPR.AC-7
pcidssReq-8.1.8
os-srgSRG-OS-000029-GPOS-00010, SRG-OS-000031-GPOS-00012
cis1.7.4, 1.7.5
pcidss48.2.8, 8.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)


inactivity_timeout_value='900'


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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "uint32 ${inactivity_timeout_value}")"
if grep -q "^\\s*idle-delay\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*idle-delay\\s*=\\s*.*/idle-delay=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/desktop/session\\]|a\\idle-delay=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

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

Rule   Set GNOME3 Screensaver Lock Delay After Activation Period   [ref]

To activate the locking delay of the screensaver in the GNOME3 desktop when the screensaver is activated, add or set lock-delay to uint32 5 in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
lock-delay=uint32 5
         
After the settings have been set, run dconf update.
Rationale:
A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to logout because of the temporary nature of the absense.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_delay
References:
cis-csc1, 12, 15, 16
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.10
disaCCI-000057
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-11(a), CM-6(a)
nist-csfPR.AC-7
pcidssReq-8.1.8
os-srgSRG-OS-000029-GPOS-00010, SRG-OS-000031-GPOS-00012
cis1.7.4, 1.7.5
pcidss48.2.8, 8.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)


var_screensaver_lock_delay='5'


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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "uint32 ${var_screensaver_lock_delay}")"
if grep -q "^\\s*lock-delay\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*lock-delay\\s*=\\s*.*/lock-delay=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/desktop/screensaver\\]|a\\lock-delay=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

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

Rule   Enable GNOME3 Screensaver Lock After Idle Period   [ref]

To activate locking of the screensaver in the GNOME3 desktop when it is activated, add or set lock-enabled to true in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
lock-enabled=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/lock-enabled
After the settings have been set, run dconf update.
Rationale:
A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to logout because of the temporary nature of the absense.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_enabled
References:
cis-csc1, 12, 15, 16
cjis5.5.5
cobit5DSS05.04, DSS05.10, DSS06.10
cui3.1.10
disaCCI-000057, CCI-000056
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
nistCM-6(a)
nist-csfPR.AC-7
pcidssReq-8.1.8
os-srgSRG-OS-000028-GPOS-00009, SRG-OS-000030-GPOS-00011
cis1.7.4, 1.7.5
pcidss48.2.8, 8.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)



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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*lock-enabled\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*lock-enabled\\s*=\\s*.*/lock-enabled=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/desktop/screensaver\\]|a\\lock-enabled=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/desktop/screensaver/lock-enabled$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|local.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/local.d/locks"

mkdir -p "${LOCKSFOLDER}"

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

if ! grep -qr "^/org/gnome/desktop/screensaver/lock-enabled$" /etc/dconf/db/local.d/
then
    echo "/org/gnome/desktop/screensaver/lock-enabled" >> "/etc/dconf/db/local.d/locks/00-security-settings-lock"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Sudo   Group contains 5 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:
$ apt-get 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
cis5.2.1
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "sudo"

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


[[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: '"linux-base" 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
cis5.2.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'sudo' 2>/dev/null | grep -q installed; 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
cis5.2.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'sudo' 2>/dev/null | grep -q installed; 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   Ensure Users Re-Authenticate for Privilege Escalation - sudo !authenticate   [ref]

The sudo !authenticate option, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the !authenticate option does not exist in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/.
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_remove_no_authenticate
References:
cis-csc1, 12, 15, 16, 5
cobit5DSS05.04, DSS05.10, DSS06.03, DSS06.10
disaCCI-004895
isa-62443-20094.3.3.5.1, 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
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
iso27001-2013A.18.1.4, 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-11, CM-6(a)
nist-csfPR.AC-1, PR.AC-7
os-srgSRG-OS-000373-GPOS-00156, SRG-OS-000373-GPOS-00157, SRG-OS-000373-GPOS-00158
cis5.2.5

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

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

    /usr/sbin/visudo -cf $f &> /dev/null || echo "Fail to validate $f with visudo"
  fi
done

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Find /etc/sudoers.d/ files
  ansible.builtin.find:
    paths:
    - /etc/sudoers.d/
  register: sudoers
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-11
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_remove_no_authenticate

- name: Remove lines containing !authenticate from sudoers files
  ansible.builtin.replace:
    regexp: (^(?!#).*[\s]+\!authenticate.*$)
    replace: '# \g<1>'
    path: '{{ item.path }}'
    validate: /usr/sbin/visudo -cf %s
  with_items:
  - path: /etc/sudoers
  - '{{ sudoers.files }}'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-11
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_remove_no_authenticate

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
cis5.2.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'sudo' 2>/dev/null | grep -q installed; then

var_sudo_timestamp_timeout='15'


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 15
  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   Account and Access Control   Group contains 14 groups and 63 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 Ubuntu 24.04.
Group   Warning Banners for System Accesses   Group contains 1 group and 13 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.
Group   Implement a GUI Warning Banner   Group contains 2 rules

Rule   Enable GNOME3 Login Warning Banner   [ref]

In the default graphical environment, displaying a login warning banner in the GNOME Display Manager's login screen can be enabled on the login screen by setting banner-message-enable to true.

To enable, add or edit banner-message-enable to /etc/dconf/db/gdm.d/00-security-settings. For example:
[org/gnome/login-screen]
banner-message-enable=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/banner-message-enable
After the settings have been set, run dconf update. The banner text must also be set.
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.

For U.S. Government systems, 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_dconf_gnome_banner_enabled
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(b), AC-8(c)
nist-csfPR.AC-7
os-srgSRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088
cis1.7.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'gdm3' 2>/dev/null | grep -q installed; then

mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/user

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:local" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:local\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/local.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
mkdir -p /etc/dconf/profile
dconf_profile_path=/etc/dconf/profile/gdm

[[ -s "${dconf_profile_path}" ]] || echo > "${dconf_profile_path}"

if ! grep -Pzq "(?s)^\s*user-db:user.*\n\s*system-db:gdm" "${dconf_profile_path}"; then
    sed -i --follow-symlinks "1s/^/user-db:user\nsystem-db:gdm\n/" "${dconf_profile_path}"
fi

# Make sure the corresponding directories exist
mkdir -p /etc/dconf/db/gdm.d

# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/profile
(umask 0022 && dconf update)
# Duplicate the setting also in 'greeter.dconf-defaults' for consistency with
# 'dconf_gnome_login_banner_text' and better alignment with STIG V1R1.
if [ -e "/etc/gdm3/greeter.dconf-defaults" ] ; then
    
    LC_ALL=C sed -i "/^\s*banner\-message\-enable/Id" "/etc/gdm3/greeter.dconf-defaults"
else
    touch "/etc/gdm3/greeter.dconf-defaults"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/gdm3/greeter.dconf-defaults"

cp "/etc/gdm3/greeter.dconf-defaults" "/etc/gdm3/greeter.dconf-defaults.bak"
# Insert after the line matching the regex '\[org/gnome/login-screen\]'
line_number="$(LC_ALL=C grep -n "\[org/gnome/login-screen\]" "/etc/gdm3/greeter.dconf-defaults.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '\[org/gnome/login-screen\]', insert at
    # the end of the file.
    printf '%s\n' "banner-message-enable=true" >> "/etc/gdm3/greeter.dconf-defaults"
else
    head -n "$(( line_number ))" "/etc/gdm3/greeter.dconf-defaults.bak" > "/etc/gdm3/greeter.dconf-defaults"
    printf '%s\n' "banner-message-enable=true" >> "/etc/gdm3/greeter.dconf-defaults"
    tail -n "+$(( line_number + 1 ))" "/etc/gdm3/greeter.dconf-defaults.bak" >> "/etc/gdm3/greeter.dconf-defaults"
fi
# Clean up after ourselves.
rm "/etc/gdm3/greeter.dconf-defaults.bak"


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

mkdir -p "${DBDIR}"

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

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

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*banner-message-enable\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*banner-message-enable\\s*=\\s*.*/banner-message-enable=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/login-screen\\]|a\\banner-message-enable=${escaped_value}" "${DCONFFILE}"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/login-screen/banner-message-enable$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|gdm.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/gdm.d/locks"

mkdir -p "${LOCKSFOLDER}"

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

if ! grep -qr "^/org/gnome/login-screen/banner-message-enable$" /etc/dconf/db/gdm.d/
then
    echo "/org/gnome/login-screen/banner-message-enable" >> "/etc/dconf/db/gdm.d/locks/00-security-settings-lock"
fi
# Make sure permissions allow regular users to read dconf settings.
# Also define the umask to avoid `dconf update` changing permissions.
chmod -R u=rwX,go=rX /etc/dconf/db
(umask 0022 && dconf update)

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

Rule   Ensure Local Login Warning Banner Is Configured Properly   [ref]

To configure the system local login warning banner edit the /etc/issue file. The contents of this file is displayed to users prior to login to local terminals. Replace the default text with a message compliant with the local site policy. The message should not contain information about operating system version, release, kernel version or patch level. The recommended banner text can be tailored in the XCCDF Value xccdf_org.ssgproject.content_value_cis_banner_text:
Authorized users only. All activity may be monitored and reported.
Rationale:
Warning messages inform users who are attempting to login to the system of their legal status regarding the system and must include the name of the organization that owns the system and any monitoring policies that are in place. Displaying OS and patch level information in login banners also has the side effect of providing detailed system information to attackers attempting to target specific exploits of a system. Authorized users can easily get this information by running the uname -a command once they have logged in.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_issue_cis
References:
cis1.6.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

cis_banner_text='Authorized users only. All activity may be monitored and reported.'

echo "$cis_banner_text" > "/etc/issue"

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:
  - banner_etc_issue_cis
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value cis_banner_text # promote to variable
  set_fact:
    cis_banner_text: !!str Authorized users only. All activity may be monitored and reported.
  tags:
    - always

- name: Ensure Local Login Warning Banner Is Configured Properly - Copy using inline
    content
  ansible.builtin.copy:
    content: '{{ cis_banner_text }}'
    dest: /etc/issue
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - banner_etc_issue_cis
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure Remote Login Warning Banner Is Configured Properly   [ref]

To configure the system remote login warning banner edit the /etc/issue.net file. The contents of this file is displayed to users prior to login from remote connections. Replace the default text with a message compliant with the local site policy. The message should not contain information about operating system version, release, kernel version or patch level. The recommended banner text can be tailored in the XCCDF Value xccdf_org.ssgproject.content_value_cis_banner_text:
Authorized users only. All activity may be monitored and reported.
Rationale:
Warning messages inform users who are attempting to login to the system of their legal status regarding the system and must include the name of the organization that owns the system and any monitoring policies that are in place. Displaying OS and patch level information in login banners also has the side effect of providing detailed system information to attackers attempting to target specific exploits of a system. Authorized users can easily get this information by running the uname -a command once they have logged in.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_issue_net_cis
References:
cis1.6.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

cis_banner_text='Authorized users only. All activity may be monitored and reported.'

echo "$cis_banner_text" > "/etc/issue.net"

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:
  - banner_etc_issue_net_cis
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value cis_banner_text # promote to variable
  set_fact:
    cis_banner_text: !!str Authorized users only. All activity may be monitored and reported.
  tags:
    - always

- name: Ensure Remote Login Warning Banner Is Configured Properly - Copy using inline
    content
  ansible.builtin.copy:
    content: '{{ cis_banner_text }}'
    dest: /etc/issue.net
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - banner_etc_issue_net_cis
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

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:
cis1.6.5

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:
cis1.6.6
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:
cis1.6.4

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:
cis1.6.5

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:
cis1.6.6
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:
cis1.6.4

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:
cis1.6.5

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:
cis1.6.6
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:
cis1.6.4

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 16 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 1 rule
[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   Verify pam_pwhistory module is activated   [ref]

The pam_pwhistory.so module is part of the Pluggable Authentication Modules (PAM) framework designed to increase password security. It works by storing a history of previously used passwords for each user, ensuring users cannot alternate between the same passwords too frequently.

This module is incompatible with Kerberos. Furthermore, its usage with NIS or LDAP is generally impractical, as other machines can not access local password histories.
Rationale:
Enforcing strong passwords increases the difficulty and resources required for password compromise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_pwhistory_enabled
References:
cis5.3.2.4

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

if [ -f /usr/bin/authselect ]; then
    if authselect list-features sssd | grep -q with-pwhistory; 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-pwhistory

        authselect apply-changes -b
    else
        
        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=$(basename "cac_pwhistory")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
        
        if ! grep -qP "^\s*password\s+requisite\s+pam_pwhistory.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_pwhistory.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
                # The control is updated only if one single line matches.
                sed -i -E --follow-symlinks "s/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1requisite \2/" "$PAM_FILE_PATH"
            else
                echo "password    requisite    pam_pwhistory.so" >> "$PAM_FILE_PATH"
            fi
        fi
    fi
else

conf_name=cac_pwhistory
conf_path="/usr/share/pam-configs"

if [ ! -f "$conf_path"/"$conf_name" ]; then
    cat << EOF > "$conf_path"/"$conf_name"
Name: pwhistory password history checking
Default: yes
Priority: 1024
Password-Type: Primary
Password: requisite pam_pwhistory.so remember=24 enforce_for_root try_first_pass use_authtok
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update

fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Set Password Quality Requirements   Group contains 1 group and 12 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 12 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 Digit Characters   [ref]

The pam_pwquality module's dcredit parameter controls requirements for usage of digits in a password. When set to a negative number, any password will be required to contain that many digits. When set to a positive number, pam_pwquality will grant +1 additional length credit for each digit. Modify the dcredit setting in /etc/security/pwquality.conf to require the use of a digit in 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 digits makes password guessing attacks more difficult by ensuring a larger search space.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_dcredit
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
osppFMT_SMF_EXT.1
pcidssReq-8.2.3
os-srgSRG-OS-000071-GPOS-00039
anssiR31
cis5.3.3.2.3
pcidss48.3.6, 8.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_dcredit='-1'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^dcredit")

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

# 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 "^dcredit\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^dcredit\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_dcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_dcredit # promote to variable
  set_fact:
    var_password_pam_dcredit: !!str -1
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Digit Characters - Check
    if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_dcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Digit Characters - Remediation
    where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Digit Characters - Ensure
      pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_dcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Digit Characters - Ensure
    PAM variable dcredit is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*dcredit
    line: dcredit = {{ var_password_pam_dcredit }}
  when: '"libpam-runtime" 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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_dcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure PAM Enforces Password Requirements - Prevent the Use of Dictionary Words   [ref]

The pam_pwquality module's dictcheck check if passwords contains dictionary words. When dictcheck is set to 1 passwords will be checked for dictionary words.
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.

Passwords with dictionary words may be more vulnerable to password-guessing attacks.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_dictcheck
References:
disaCCI-000366
nistIA-5(c), IA-5(1)(a), CM-6(a), IA-5(4)
os-srgSRG-OS-000480-GPOS-00225, SRG-OS-000072-GPOS-00040
cis5.3.3.2.6

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_dictcheck='1'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^dictcheck")

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

# 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 "^dictcheck\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^dictcheck\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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_dictcheck
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_dictcheck # promote to variable
  set_fact:
    var_password_pam_dictcheck: !!str 1
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Prevent the Use of Dictionary
    Words - Check if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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_dictcheck
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Prevent the Use of Dictionary
    Words - Remediation where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Prevent the Use of Dictionary
      Words - Ensure pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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_dictcheck
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Prevent the Use of Dictionary
    Words - Ensure PAM variable dictcheck is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*dictcheck
    line: dictcheck = {{ var_password_pam_dictcheck }}
  when: '"libpam-runtime" 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_dictcheck
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

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

The pam_pwquality module's difok parameter sets the number of characters in a password that must not be present in and old password during a password change.

Modify the difok setting in /etc/security/pwquality.conf to equal 2 to require differing 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 different characters during password changes ensures that newly changed passwords should not resemble previously compromised ones. Note that passwords which are changed on compromised systems will still be compromised, however.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_difok
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
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)(b), CM-6(a), IA-5(4)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
os-srgSRG-OS-000072-GPOS-00040
cis5.3.3.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_difok='2'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^difok")

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

# 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 "^difok\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^difok\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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)(b)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_difok
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_difok # promote to variable
  set_fact:
    var_password_pam_difok: !!str 2
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Different Characters -
    Check if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(b)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_difok
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Different Characters -
    Remediation where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Different Characters
      - Ensure pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(b)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_difok
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Different Characters -
    Ensure PAM variable difok is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*difok
    line: difok = {{ var_password_pam_difok }}
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(b)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_difok
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure PAM Enforces Password Requirements - Enforcing   [ref]

Verify that the operating system uses "pwquality" to enforce the password complexity rules. Verify the pwquality module is being enforced by operating system by running the following command:
$ grep -i enforcing /etc/security/pwquality.conf
enforcing = 1
If the value of "enforcing" is not "1" or the line is commented out, this is a finding.
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. Using enforcing=1 ensures "pwquality" enforces complex password construction configuration and has the ability to limit brute-force attacks on the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_enforcing
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00225
cis5.3.3.2.7

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_enforcing='1'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^enforcing")

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

# 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 "^enforcing\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^enforcing\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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:
  - accounts_password_pam_enforcing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_enforcing # promote to variable
  set_fact:
    var_password_pam_enforcing: !!str 1
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Enforcing - Check if system relies
    on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - accounts_password_pam_enforcing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Enforcing - Remediation where
    pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Enforcing - Ensure pam-auth-update
      profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  tags:
  - accounts_password_pam_enforcing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Enforcing - Ensure PAM variable
    enforcing is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*enforcing
    line: enforcing = {{ var_password_pam_enforcing }}
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - accounts_password_pam_enforcing
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure PAM Enforces Password Requirements - Minimum Lowercase Characters   [ref]

The pam_pwquality module's lcredit parameter controls requirements for usage of lowercase letters in a password. When set to a negative number, any password will be required to contain that many lowercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each lowercase character. Modify the lcredit setting in /etc/security/pwquality.conf to require the use of a lowercase character in 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 possble combinations that need to be tested before the password is compromised. Requiring a minimum number of lowercase characters makes password guessing attacks more difficult by ensuring a larger search space.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_lcredit
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
osppFMT_SMF_EXT.1
pcidssReq-8.2.3
os-srgSRG-OS-000070-GPOS-00038
anssiR31
cis5.3.3.2.3
pcidss48.3.6, 8.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_lcredit='-1'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^lcredit")

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

# 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 "^lcredit\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^lcredit\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_lcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_lcredit # promote to variable
  set_fact:
    var_password_pam_lcredit: !!str -1
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Lowercase Characters -
    Check if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_lcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Lowercase Characters -
    Remediation where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Lowercase Characters
      - Ensure pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_lcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Lowercase Characters -
    Ensure PAM variable lcredit is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*lcredit
    line: lcredit = {{ var_password_pam_lcredit }}
  when: '"libpam-runtime" 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)
  - PCI-DSS-Req-8.2.3
  - PCI-DSSv4-8.3
  - PCI-DSSv4-8.3.6
  - accounts_password_pam_lcredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Set Password Maximum Consecutive Repeating Characters   [ref]

The pam_pwquality module's maxrepeat parameter controls requirements for consecutive repeating characters. When set to a positive number, it will reject passwords which contain more than that number of consecutive characters. Modify the maxrepeat setting in /etc/security/pwquality.conf to equal 3 to prevent a run of (3 + 1) or more identical characters.
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.

Passwords with excessive repeating characters may be more vulnerable to password-guessing attacks.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_maxrepeat
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
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), CM-6(a), IA-5(4)
nist-csfPR.AC-1, PR.AC-6, PR.AC-7
os-srgSRG-OS-000072-GPOS-00040
cis5.3.3.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_maxrepeat='3'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^maxrepeat")

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

# 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 "^maxrepeat\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^maxrepeat\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_maxrepeat
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_maxrepeat # promote to variable
  set_fact:
    var_password_pam_maxrepeat: !!str 3
  tags:
    - always

- name: Set Password Maximum Consecutive Repeating Characters - Check if system relies
    on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_maxrepeat
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Password Maximum Consecutive Repeating Characters - Remediation where
    pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Set Password Maximum Consecutive Repeating Characters - Ensure pam-auth-update
      profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_maxrepeat
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Password Maximum Consecutive Repeating Characters - Ensure PAM variable
    maxrepeat is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*maxrepeat
    line: maxrepeat = {{ var_password_pam_maxrepeat }}
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_maxrepeat
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Limit the maximum number of sequential characters in passwords   [ref]

The pwquality maxsequence setting defines the maximum allowable length for consecutive character sequences in a new password. Such sequences can be, e.g., 123 or abc. If the value is set to 0, this check will be turned off.

Note: Passwords that consist mainly of such sequences are unlikely to meet the simplicity criteria unless the sequence constitutes only a small portion of the overall password.
Rationale:
Use of a strong 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 important factor that determines the duration required to crack it. A more intricate password results in a larger number of potential combinations that must be tested before successfully compromising the password.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_maxsequence
References:
cis5.3.3.2.5

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_maxsequence='3'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^maxsequence")

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

# 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 "^maxsequence\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^maxsequence\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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:
  - accounts_password_pam_maxsequence
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_maxsequence # promote to variable
  set_fact:
    var_password_pam_maxsequence: !!str 3
  tags:
    - always

- name: Limit the maximum number of sequential characters in passwords - Check if
    system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - accounts_password_pam_maxsequence
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Limit the maximum number of sequential characters in passwords - Remediation
    where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Limit the maximum number of sequential characters in passwords - Ensure
      pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  tags:
  - accounts_password_pam_maxsequence
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Limit the maximum number of sequential characters in passwords - Ensure PAM
    variable maxsequence is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*maxsequence
    line: maxsequence = {{ var_password_pam_maxsequence }}
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - accounts_password_pam_maxsequence
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

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
cis5.3.3.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_minclass='4'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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 -
    Check if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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

- name: Ensure PAM Enforces Password Requirements - Minimum Different Categories -
    Remediation where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Different Categories
      - Ensure pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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: 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: '"libpam-runtime" 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
cis5.3.3.2.2
pcidss48.3.6, 8.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_minlen='14'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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 - Check if system
    relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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

- name: Ensure PAM Enforces Password Requirements - Minimum Length - Remediation where
    pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Length - Ensure pam-auth-update
      profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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: 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: '"libpam-runtime" 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 - Minimum Special Characters   [ref]

The pam_pwquality module's ocredit= parameter controls requirements for usage of special (or "other") characters in a password. When set to a negative number, any password will be required to contain that many special characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each special character. Modify the ocredit setting in /etc/security/pwquality.conf to equal -1 to require use of a special character in 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 special characters makes password guessing attacks more difficult by ensuring a larger search space.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_ocredit
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
osppFMT_SMF_EXT.1
os-srgSRG-OS-000266-GPOS-00101
anssiR31
cis5.3.3.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_ocredit='-1'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^ocredit")

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

# 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 "^ocredit\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^ocredit\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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_ocredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_ocredit # promote to variable
  set_fact:
    var_password_pam_ocredit: !!str -1
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Special Characters - Check
    if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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_ocredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Special Characters - Remediation
    where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Special Characters -
      Ensure pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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_ocredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Special Characters - Ensure
    PAM variable ocredit is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*ocredit
    line: ocredit = {{ var_password_pam_ocredit }}
  when: '"libpam-runtime" 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_ocredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Verify pam_pwquality module is activated   [ref]

The pam_pwquality.so module ensures password quality by evaluating user-created passwords against a system dictionary and a set of rules designed to detect weak choices. Originally derived from the pam_cracklib module, this module is backward-compatible with options of pam_cracklib.

The module's process includes prompting the user for a password, checking its strength, and if it meets the criteria requesting the password again for confirmation. If both entries match, the password is passed to subsequent modules to be set as the new authentication token.
Rationale:
Strong passwords significantly increase the time and effort required for unauthorized access, increasing overall system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_pwquality_enabled
References:
cis5.3.2.3

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update

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

Rule   Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters   [ref]

The pam_pwquality module's ucredit= parameter controls requirements for usage of uppercase letters in a password. When set to a negative number, any password will be required to contain that many uppercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each uppercase character. Modify the ucredit setting in /etc/security/pwquality.conf to require the use of an uppercase character in 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.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_ucredit
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
osppFMT_SMF_EXT.1
pcidssReq-8.2.3
os-srgSRG-OS-000069-GPOS-00037, SRG-OS-000070-GPOS-00038
anssiR31
cis5.3.3.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_password_pam_ucredit='-1'







conf_name=cac_pwquality
if [ ! -f /usr/share/pam-configs/"$conf_name" ]; then
    cat << EOF > /usr/share/pam-configs/"$conf_name"
Name: Pwquality password strength checking
Default: yes
Priority: 1025
Conflicts: cracklib, pwquality
Password-Type: Primary
Password:
    requisite                   pam_pwquality.so
EOF
fi

DEBIAN_FRONTEND=noninteractive pam-auth-update


# 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' <<< "^ucredit")

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

# 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 "^ucredit\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^ucredit\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    if [[ -s "/etc/security/pwquality.conf" ]] && [[ -n "$(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)
  - PCI-DSS-Req-8.2.3
  - accounts_password_pam_ucredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_ucredit # promote to variable
  set_fact:
    var_password_pam_ucredit: !!str -1
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters -
    Check if system relies on pam-auth-update tool
  ansible.builtin.stat:
    path: /usr/sbin/pam-auth-update
  register: result_pam_auth_update_present
  when: '"libpam-runtime" 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)
  - PCI-DSS-Req-8.2.3
  - accounts_password_pam_ucredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters -
    Remediation where pam-auth-update tool is present
  block:

  - name: Check if /usr/share/pam-configs/cac_pwquality exists
    stat:
      path: /usr/share/pam-configs/cac_pwquality
    register: pwquality_file_stat

  - name: Put the content into /usr/share/pam-configs/cac_pwquality if it does not
      exist
    copy:
      dest: /usr/share/pam-configs/cac_pwquality
      content: |
        Name: Pwquality password strength checking
        Default: yes
        Priority: 1024
        Conflicts: cracklib
        Password-Type: Primary
        Password:
          requisite           pam_pwquality.so retry=3
      force: true
    when: not pwquality_file_stat.stat.exists

  - name: Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters
      - Ensure pam-auth-update profile changes are applied
    ansible.builtin.command:
      cmd: pam-auth-update --enable cac_pwquality
  when:
  - '"libpam-runtime" in ansible_facts.packages'
  - result_pam_auth_update_present.stat.exists
  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)
  - PCI-DSS-Req-8.2.3
  - accounts_password_pam_ucredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure PAM Enforces Password Requirements - Minimum Uppercase Characters -
    Ensure PAM variable ucredit is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*ucredit
    line: ucredit = {{ var_password_pam_ucredit }}
  when: '"libpam-runtime" 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)
  - PCI-DSS-Req-8.2.3
  - accounts_password_pam_ucredit
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
Group   Set Password Hashing Algorithm   Group contains 1 rule
[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|YESCRYPT as the hashing algorithm:
ENCRYPT_METHOD SHA512|YESCRYPT
         
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
cis5.4.1.4
pcidss48.3.2, 8.3

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'login' 2>/dev/null | grep -q installed; then

var_password_hashing_algorithm='SHA512|YESCRYPT'


# 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   Install pam_pwquality Package   [ref]

The libpam-pwquality package can be installed with the following command:
$ apt-get install libpam-pwquality
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. "pwquality" enforces complex password construction configuration and has the ability to limit brute-force attacks on the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_pam_pwquality_installed
References:
disaCCI-000366
os-srgSRG-OS-000480-GPOS-00225
cis5.3.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "libpam-pwquality"

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


[[packages]]
name = "libpam-pwquality"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_pam_pwquality_installed

- name: Ensure libpam-pwquality is installed
  package:
    name: libpam-pwquality
    state: present
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_pam_pwquality_installed

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include install_libpam-pwquality

class install_libpam-pwquality {
  package { 'libpam-pwquality':
    ensure => 'installed',
  }
}

Rule   Verify pam_unix module is activated   [ref]

pam_unix is the standard Unix authentication module. It uses standard calls from the system's libraries to retrieve and set account information as well as authentication. Usually this is obtained from the /etc/passwd and if shadow is enabled, the /etc/shadow file as well.

The account component performs the task of establishing the status of the user's account and password based on the following shadow elements: expire, last_change, max_change, min_change, warn_change. In the case of the latter, it may offer advice to the user on changing their password or, through the PAM_AUTHTOKEN_REQD return, delay giving service to the user until they have established a new password. The entries listed above are documented in the shadow(5) manual page. Should the user's record not contain one or more of these entries, the corresponding shadow check is not performed.

The authentication component performs the task of checking the users credentials (password). The default action of this module is to not permit the user access to a service if their official password is blank.
Rationale:
The system should only provide access after performing authentication of a user.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_unix_enabled
References:
cis5.3.2.1

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

conf_name=cac_unix
conf_path="/usr/share/pam-configs"

if [ ! -f "$conf_path"/"$conf_name" ]; then
    if [ -f "$conf_path"/unix ]; then
        if grep -q "$(md5sum "$conf_path"/unix | cut -d ' ' -f 1)" /var/lib/dpkg/info/libpam-runtime.md5sums;then
            cp "$conf_path"/unix "$conf_path"/"$conf_name"
            sed -i '/Default: yes/a Priority: 257\
Conflicts: unix' "$conf_path"/"$conf_name"
            DEBIAN_FRONTEND=noninteractive pam-auth-update
        else
            echo "Not applicable - checksum of $conf_path/unix does not match the original." >&2
        fi
    else
        echo "Not applicable - $conf_path/unix does not exist" >&2
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Protect Accounts by Restricting Password-Based Login   Group contains 4 groups and 21 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 3 rules

Rule   Ensure shadow Group is Empty   [ref]

The shadow group allows system programs which require access the ability to read the /etc/shadow file. No users should be assigned to the shadow group.
Warning:  This rule remediation will ensure the group membership is empty in /etc/group. To avoid any disruption the remediation won't change the primary group of users in /etc/passwd if any user has the shadow GID as primary group.
Rationale:
Any users assigned to the shadow group would be granted read access to the /etc/shadow file. If attackers can gain read access to the /etc/shadow file, they can easily run a password cracking program against the hashed passwords to break them. Other security information that is stored in the /etc/shadow file (such as expiration) could also be useful to subvert additional user accounts.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ensure_shadow_group_empty
References:
pcidssReq-8.2.1
cis7.2.4
pcidss48.3.2, 8.3


sed -ri 's/(^shadow:[^:]*:[^:]*:)([^:]+$)/\1/' /etc/group
Group   Set Password Expiration Parameters   Group contains 3 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
cis5.4.1.1
pcidss48.3.9, 8.3

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

var_accounts_maximum_age_login_defs='365'


while IFS= read -r i; do
    
    chage -M $var_accounts_maximum_age_login_defs $i

done <   <(awk -v var="$var_accounts_maximum_age_login_defs" -F: '(/^[^:]+:[^!*]/ && ($5 > var || $5 == "")) {print $1}' /etc/shadow)
Group   Verify Proper Storage and Existence of Password Hashes   Group contains 6 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
cis7.2.1
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:
cis5.4.1.6
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
cis7.2.3
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
cis7.2.2
pcidss42.2.2, 2.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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:
cis7.2.10

Rule   Verify No netrc Files Exist   [ref]

The .netrc files contain login information used to auto-login into FTP servers and reside in the user's home directory. These files may contain unencrypted passwords to remote FTP servers making them susceptible to access by unauthorized users and should not be used. Any .netrc files should be removed.
Rationale:
Unencrypted passwords for remote FTP servers may be stored in .netrc files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_netrc_files
References:
cis-csc1, 11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
disaCCI-000196
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
iso27001-2013A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nerc-cipCIP-003-8 R1.3, CIP-003-8 R3, CIP-003-8 R3.1, CIP-003-8 R3.2, CIP-003-8 R3.3, CIP-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-5(h), IA-5(1)(c), CM-6(a), IA-5(7)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3
cis7.2.10
Group   Restrict Root Logins   Group contains 6 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
cis5.4.2.1
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   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:
cis5.2.7
pcidss42.2.6, 2.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_pam_wheel_group_for_su='sugroup'


if ! grep -q "^${var_pam_wheel_group_for_su}:[^:]*:[^:]*:[^:]*" /etc/group; then
    groupadd ${var_pam_wheel_group_for_su}
fi

# group must be empty
gpasswd -M '' ${var_pam_wheel_group_for_su}

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
  - ensure_pam_wheel_group_empty
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_pam_wheel_group_for_su # promote to variable
  set_fact:
    var_pam_wheel_group_for_su: !!str sugroup
  tags:
    - always

- name: Ensure the Group Used by pam_wheel.so Module Exists on System and is Empty
    - Ensure {{ var_pam_wheel_group_for_su }} Group Exists
  ansible.builtin.group:
    name: '{{ var_pam_wheel_group_for_su }}'
    state: present
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - ensure_pam_wheel_group_empty
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure the Group Used by pam_wheel.so Module Exists on System and is Empty
    - Ensure {{ var_pam_wheel_group_for_su }} Group is Empty
  ansible.builtin.lineinfile:
    path: /etc/group
    regexp: ^({{ var_pam_wheel_group_for_su }}:[^:]+:[0-9]+:).*$
    line: \1
    backrefs: true
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - ensure_pam_wheel_group_empty
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure root account access is controlled   [ref]

There are a number of methods to access the root account directly. Without a password set any user would be able to gain access and thus control over the entire system.
Warning:  This rule doesn't come with a remediation, as the exact requirement allows root to either have a password or be locked.
Rationale:
Access to root should be secured at all times.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ensure_root_access_controlled
References:
cis5.4.2.4

Rule   Verify Only Group Root Has GID 0   [ref]

If any group other than root has a GID of 0, this misconfiguration should be investigated and the groups other than root should be removed or have their GID changed.
Warning:  This rule doesn't come with a remediation. The removal of groups from a system or reassigning the GID is considered too disruptive.
Rationale:
Ensuring that only the root group has a GID of 0 helps prevent root group owned files from becoming accidentally accessible to non-privileged users.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_groups_no_zero_gid_except_root
References:
cis5.4.2.3

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
cis5.4.2.7
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:
cis5.2.7
pcidss42.2.6, 2.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

var_pam_wheel_group_for_su='sugroup'


PAM_CONF=/etc/pam.d/su

pamstr=$(grep -P '^auth\s+required\s+pam_wheel\.so\s+(?=[^#]*\buse_uid\b)(?=[^#]*\bgroup=)' ${PAM_CONF})
if [ -z "$pamstr" ]; then
    sed -Ei '/^auth\b.*\brequired\b.*\bpam_wheel\.so/d' ${PAM_CONF} # remove any remaining uncommented pam_wheel.so line
    sed -Ei "/^auth\s+sufficient\s+pam_rootok\.so.*$/a auth             required        pam_wheel.so use_uid group=${var_pam_wheel_group_for_su}" ${PAM_CONF}
else
    group_val=$(echo -n "$pamstr" | grep -Eo '\bgroup=[_a-z][-0-9_a-z]*' | cut -d '=' -f 2)
    if [ -z "${group_val}" ] || [ ${group_val} != ${var_pam_wheel_group_for_su} ]; then
        sed -Ei "s/(^auth\s+required\s+pam_wheel.so\s+[^#]*group=)[_a-z][-0-9_a-z]*/\1${var_pam_wheel_group_for_su}/" ${PAM_CONF}
    fi
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-DSSv4-2.2
  - PCI-DSSv4-2.2.6
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - use_pam_wheel_group_for_su
- name: XCCDF Value var_pam_wheel_group_for_su # promote to variable
  set_fact:
    var_pam_wheel_group_for_su: !!str sugroup
  tags:
    - always

- name: Enforce Usage of pam_wheel with Group Parameter for su Authentication - Add
    the group to the /etc/pam.d/su file
  ansible.builtin.lineinfile:
    path: /etc/pam.d/su
    state: present
    regexp: ^[\s]*#[\s]*auth[\s]+required[\s]+pam_wheel\.so[\s]+use_uid group=$
    line: auth             required        pam_wheel.so use_uid group={{ var_pam_wheel_group_for_su
      }}
  when: '"libpam-runtime" 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
  - use_pam_wheel_group_for_su

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
cis7.2.6
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:
cis7.2.8
pcidss48.2.1, 8.2
Group   Secure Session Configuration Files for Login Accounts   Group contains 1 group and 13 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 Users Have Sensible Umask Values   Group contains 4 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/bash.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
cis5.4.3.3

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'bash' 2>/dev/null | grep -q installed; then

var_accounts_user_umask='027'






grep -q "^[^#]*\bumask" /etc/bash.bashrc && \
  sed -i -E -e "s/^([^#]*\bumask)[[:space:]]+[[:digit:]]+/\1 $var_accounts_user_umask/g" /etc/bash.bashrc
if ! [ $? -eq 0 ]; then
    echo "umask $var_accounts_user_umask" >> /etc/bash.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/bash.bashrc is already set
  ansible.builtin.lineinfile:
    path: /etc/bash.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/bash.bashrc
  ansible.builtin.replace:
    path: /etc/bash.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/bash.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
cis5.4.3.3

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   Ensure the Root Bash Umask is Set Correctly   [ref]

To ensure the root user's umask of the Bash shell is set properly, add or correct the umask setting in /root/.bashrc or /root/.bashrc to read as follows:
umask 0027
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_root
References:
cis5.4.2.6

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'bash' 2>/dev/null | grep -q installed; then

sed -i -E -e "s/^([^#]*\bumask)[[:space:]]+[[:digit:]]+/\1 0027/g" /root/.bashrc /root/.profile

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

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:
TMOUT=900
        
readonly TMOUT export TMOUT
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
cis5.4.3.2
pcidss48.6.1, 8.6

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

var_accounts_tmout='900'


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

for f in /etc/bash.bashrc /etc/profile /etc/profile.d/*.sh; do
    if grep --silent '^\s*TMOUT' $f; then
        sed -i -E "s/^(\s*)TMOUT\s*=\s*(\w|\$)*(.*)$/\1TMOUT=$var_accounts_tmout\3/g" $f
        tmout_found=1
        if ! grep --silent '^\s*readonly TMOUT' $f ; then
            echo "readonly TMOUT" >> $f
        fi
        if ! grep --silent '^\s*export TMOUT' $f ; then
            echo "export TMOUT" >> $f
        fi
    fi
done

if [ $tmout_found -eq 0 ]; then
        echo -e "\n# Set TMOUT to $var_accounts_tmout per security requirements" >> /etc/profile.d/tmout.sh
        echo "TMOUT=$var_accounts_tmout" >> /etc/profile.d/tmout.sh
        echo "readonly TMOUT" >> /etc/profile.d/tmout.sh
        echo "export 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: '"linux-base" 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: '"linux-base" 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
cis7.2.10

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: 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
cis7.2.10

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: 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
cis7.2.9

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   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
cis7.2.9

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
cis7.2.9

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 User Bash History File Has Correct Permissions   [ref]

Set the mode of the bash history file to 0600 with the following command:
$ sudo chmod 0600 /home/USER/.bash_history
Rationale:
Incorrect permissions may enable malicious users to recover other users' command history.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permission_user_bash_history
References:
cis7.2.10

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

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
        
        chmod u-sx,go= "${interactive_users_home[$i]}/.bash_history"
    fi
done

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
cis7.2.10

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

var_user_initialization_files_regex='^(\.bashrc|\.zshrc|\.cshrc|\.profile|\.bash_login|\.bash_profile)$'


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 ^(\.bashrc|\.zshrc|\.cshrc|\.profile|\.bash_login|\.bash_profile)$
  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
cis7.2.9

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   AppArmor   Group contains 4 rules
[ref]   Many security vulnerabilities result from bugs in trusted programs. A trusted program runs with privileges that attackers want to possess. The program fails to keep that trust if there is a bug in the program that allows the attacker to acquire said privilege.

AppArmor® is an application security solution designed specifically to apply privilege confinement to suspect programs. AppArmor allows the administrator to specify the domain of activities the program can perform by developing a security profile. A security profile is a listing of files that the program may access and the operations the program may perform. AppArmor secures applications by enforcing good application behavior without relying on attack signatures, so it can prevent attacks even if previously unknown vulnerabilities are being exploited.

Rule   Ensure AppArmor Utils is installed   [ref]

AppArmor provide Mandatory Access Controls.
Rationale:
Without a Mandatory Access Control system installed only the default Discretionary Access Control system will be available.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_apparmor-utils_installed
References:
cis1.3.1.1

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

DEBIAN_FRONTEND=noninteractive apt-get install -y "apparmor-utils"

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


[[packages]]
name = "apparmor-utils"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Ensure apparmor-utils is installed
  package:
    name: apparmor-utils
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_apparmor-utils_installed

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include install_apparmor-utils

class install_apparmor-utils {
  package { 'apparmor-utils':
    ensure => 'installed',
  }
}

Rule   Ensure AppArmor is installed   [ref]

AppArmor provide Mandatory Access Controls.
Rationale:
Without a Mandatory Access Control system installed only the default Discretionary Access Control system will be available.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_apparmor_installed
References:
disaCCI-001764, CCI-001774, CCI-002165, CCI-002235
os-srgSRG-OS-000368-GPOS-00154, SRG-OS-000312-GPOS-00122, SRG-OS-000312-GPOS-00123, SRG-OS-000312-GPOS-00124, SRG-OS-000324-GPOS-00125, SRG-OS-000370-GPOS-00155
anssiR45
cis1.3.1.1

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

DEBIAN_FRONTEND=noninteractive apt-get install -y "apparmor"

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Ensure apparmor is installed
  package:
    name: apparmor
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_apparmor_installed

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

class install_apparmor {
  package { 'apparmor':
    ensure => 'installed',
  }
}

Rule   All AppArmor Profiles are in enforce or complain mode   [ref]

AppArmor profiles define what resources applications are able to access. To set all profiles to either enforce or complain mode run the following command to set all profiles to enforce mode:
$ sudo aa-enforce /etc/apparmor.d/*
run the following command to set all profiles to complain mode:
$ sudo aa-complain /etc/apparmor.d/*
To list unconfined processes run the following command:
$ sudo apparmor_status | grep processes
Any unconfined processes may need to have a profile created or activated for them and then be restarted.
Rationale:
Security configuration requirements vary from site to site. Some sites may mandate a policy that is stricter than the default policy, which is perfectly acceptable. This recommendation is intended to ensure that any policies that exist on the system are activated.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_all_apparmor_profiles_in_enforce_complain_mode
References:
cis1.3.1.3

# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && { ( [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ] && dpkg-query --show --showformat='${db:Status-Status}\n' 'apparmor' 2>/dev/null | grep -q installed ); }; then

var_apparmor_mode='enforce'


# make sure apparmor-utils is installed for aa-complain and aa-enforce
DEBIAN_FRONTEND=noninteractive apt-get install -y "apparmor-utils"

# Reload all AppArmor profiles
apparmor_parser -q -r /etc/apparmor.d/

# Set the mode
APPARMOR_MODE="$var_apparmor_mode"

if [ "$APPARMOR_MODE" = "enforce" ]
then
  
  # Set all profiles to enforce mode except disabled profiles
  find /etc/apparmor.d -maxdepth 1 ! -type d -exec bash -c '[[ -e "/etc/apparmor.d/disable/$(basename "$1")" ]] || aa-enforce "$1"' _ {} \;
  
fi

if [ "$APPARMOR_MODE" = "complain" ]
then
  
  # Load all not-loaded profiles into complain mode
  apparmor_parser -a --Complain /etc/apparmor.d/
  echo "***WARNING***: This remediation will not downgrade any existing AppArmor profiles."
  
fi


UNCONFINED=$(aa-status | grep "processes are unconfined" | awk '{print $1;}')
if [ $UNCONFINED -ne 0 ];

then
  echo -e "***WARNING***: There are some unconfined processes:"
  echo -e "----------------------------"
  echo "The may need to have a profile created or activated for them and then be restarted."
  for PROCESS in "${UNCONFINED[@]}"
  do
      echo "$PROCESS"
  done
  echo -e "----------------------------"
  echo "The may need to have a profile created or activated for them and then be restarted."
fi

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

Rule   Ensure AppArmor is enabled in the bootloader configuration   [ref]

Configure AppArmor to be enabled at boot time and verify that it has not been overwritten by the bootloader boot parameters. Note: This recommendation is designed around the grub bootloader, if LILO or another bootloader is in use in your environment, enact equivalent settings.
Rationale:
AppArmor must be enabled at boot time in your bootloader configuration to ensure that the controls it provides are not overridden.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_grub2_enable_apparmor
References:
anssiR45
cis1.3.1.2

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

# Correct the form of default kernel command line in GRUB
if grep -q '^\s*GRUB_CMDLINE_LINUX=.*apparmor=.*"'  '/etc/default/grub' ; then
       # modify the GRUB command-line if an apparmor= arg already exists
       sed -i "s/\(^\s*GRUB_CMDLINE_LINUX=\".*\)apparmor=[^[:space:]]\+\(.*\"\)/\1apparmor=1\2/"  '/etc/default/grub'
# Add to already existing GRUB_CMDLINE_LINUX parameters
elif grep -q '^\s*GRUB_CMDLINE_LINUX='  '/etc/default/grub' ; then
       # no apparmor=arg is present, append it
       sed -i "s/\(^\s*GRUB_CMDLINE_LINUX=\".*\)\"/\1 apparmor=1\"/"  '/etc/default/grub'
# Add GRUB_CMDLINE_LINUX parameters line
else
       echo "GRUB_CMDLINE_LINUX=\"apparmor=1\"" >> '/etc/default/grub'
fi
# Correct the form of default kernel command line in GRUB
if grep -q '^\s*GRUB_CMDLINE_LINUX=.*security=.*"'  '/etc/default/grub' ; then
       # modify the GRUB command-line if an security= arg already exists
       sed -i "s/\(^\s*GRUB_CMDLINE_LINUX=\".*\)security=[^[:space:]]\+\(.*\"\)/\1security=apparmor\2/"  '/etc/default/grub'
# Add to already existing GRUB_CMDLINE_LINUX parameters
elif grep -q '^\s*GRUB_CMDLINE_LINUX='  '/etc/default/grub' ; then
       # no security=arg is present, append it
       sed -i "s/\(^\s*GRUB_CMDLINE_LINUX=\".*\)\"/\1 security=apparmor\"/"  '/etc/default/grub'
# Add GRUB_CMDLINE_LINUX parameters line
else
       echo "GRUB_CMDLINE_LINUX=\"security=apparmor\"" >> '/etc/default/grub'
fi


update-grub

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   GRUB2 bootloader configuration   Group contains 2 groups and 4 rules
[ref]   During the boot process, the boot loader is responsible for starting the execution of the kernel and passing options to it. The boot loader allows for the selection of different kernels - possibly on different partitions or media. The default Ubuntu 24.04 boot loader for x86 systems is called GRUB2. Options it can pass to the kernel include single-user mode, which provides root access without any authentication, and the ability to disable SELinux. To prevent local users from modifying the boot parameters and endangering security, protect the boot loader configuration with a password and ensure its configuration file's permissions are set properly.
Group   Non-UEFI GRUB2 bootloader configuration   Group contains 3 rules
[ref]   Non-UEFI GRUB2 bootloader configuration

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

The file /boot/grub/grub.cfg should be owned by the root user to prevent destruction or modification of the file. To properly set the owner of /boot/grub/grub.cfg, run the command:
$ sudo chown root /boot/grub/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
cis1.4.2
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 ] && dpkg-query --show --showformat='${db:Status-Status}\n' 'grub2-common' 2>/dev/null | grep -q installed && { dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; }; then

chown 0 /boot/grub/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/grub/grub.cfg
  stat:
    path: /boot/grub/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - '"linux-base" 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/grub/grub.cfg
  file:
    path: /boot/grub/grub.cfg
    owner: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - '"linux-base" 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/grub/grub.cfg Permissions   [ref]

File permissions for /boot/grub/grub.cfg should be set to 600. To properly set the permissions of /boot/grub/grub.cfg, run the command:
$ sudo chmod 600 /boot/grub/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
cis1.4.2
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 ] && dpkg-query --show --showformat='${db:Status-Status}\n' 'grub2-common' 2>/dev/null | grep -q installed && { dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; }; then

chmod u-xs,g-xwrs,o-xwrt /boot/grub/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/grub/grub.cfg
  stat:
    path: /boot/grub/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - '"linux-base" 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/grub/grub.cfg
  file:
    path: /boot/grub/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'
  - '"linux-base" 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   Set Boot Loader Password in grub2   [ref]

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

Since plaintext passwords are a security risk, generate a hash for the password by running the following command:
# grub2-mkpasswd-pbkdf2
When prompted, enter the password that was selected.

Using the hash from the output, modify the /etc/grub.d/40_custom file with the following content:
set superusers="boot"
password_pbkdf2 boot grub.pbkdf2.sha512.VeryLongString
NOTE: the bootloader superuser account and password MUST differ from the root account and password. Once the superuser password has been added, update the grub.cfg file by running:
update-grub 
Warning:  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Rationale:
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_grub2_password
References:
cis-csc1, 11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10
cui3.4.5
disaCCI-000213
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
iso27001-2013A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5
nistCM-6(a)
nist-csfPR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3
os-srgSRG-OS-000080-GPOS-00048
anssiR5
cis1.4.1
Group   UEFI GRUB2 bootloader configuration   Group contains 1 rule
[ref]   UEFI GRUB2 bootloader configuration
Warning:  UEFI generally uses vfat file systems, which does not support Unix-style permissions managed by chmod command. In this case, in order to change file permissions for files within /boot/efi it is necessary to update the mount options in /etc/fstab file and reboot the system.

Rule   Set the UEFI Boot Loader Password   [ref]

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

Since plaintext passwords are a security risk, generate a hash for the password by running the following command:
# grub2-mkpasswd-pbkdf2
When prompted, enter the password that was selected.

Using the hash from the output, modify the /etc/grub.d/40_custom file with the following content:
set superusers="boot"
password_pbkdf2 boot grub.pbkdf2.sha512.VeryLongString
NOTE: the bootloader superuser account and password MUST differ from the root account and password. Once the superuser password has been added, update the grub.cfg file by running:
update-grub 
Warning:  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Rationale:
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_grub2_uefi_password
References:
cis-csc11, 12, 14, 15, 16, 18, 3, 5
cobit5DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06
cui3.4.5
disaCCI-000213
hipaa164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii)
isa-62443-20094.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7
iso27001-2013A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5
nistCM-6(a)
nist-csfPR.AC-4, PR.AC-6, PR.PT-3
osppFIA_UAU.1
os-srgSRG-OS-000080-GPOS-00048
anssiR5
cis1.4.1
Group   Configure Syslog   Group contains 2 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 Ubuntu 24.04, 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   systemd-journald   Group contains 8 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   Install systemd-journal-remote Package   [ref]

Journald (via systemd-journal-remote ) supports the ability to send log events it gathers to a remote log host or to receive messages from remote hosts, thus enabling centralised log management.
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_package_systemd-journal-remote_installed
References:
os-srgSRG-OS-000479-GPOS-00224
cis6.1.2.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "systemd-journal-remote"

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


[[packages]]
name = "systemd-journal-remote"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_systemd-journal-remote_installed

- name: Ensure systemd-journal-remote is installed
  package:
    name: systemd-journal-remote
    state: present
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_systemd-journal-remote_installed

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include install_systemd-journal-remote

class install_systemd-journal-remote {
  package { 'systemd-journal-remote':
    ensure => 'installed',
  }
}

Rule   Enable systemd-journal-upload Service   [ref]

Ubuntu 24.04 must offload rsyslog messages for networked systems in real time and offload standalone systems at least weekly. The systemd-journal-upload service can be enabled with the following command:
$ sudo systemctl enable systemd-journal-upload.service
Rationale:
Ubuntu 24.04 must offload rsyslog messages for networked systems in real time and offload standalone systems at least weekly.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_systemd-journal-upload_enabled
References:
os-srgSRG-OS-000479-GPOS-00224
cis6.1.2.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'systemd-journal-upload.service'
"$SYSTEMCTL_EXEC" start 'systemd-journal-upload.service'
"$SYSTEMCTL_EXEC" enable 'systemd-journal-upload.service'

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


[customizations.services]
enabled = ["systemd-journal-upload"]

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_systemd-journal-upload_enabled

- name: Enable systemd-journal-upload Service - Enable service systemd-journal-upload
  block:

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

  - name: Enable systemd-journal-upload Service - Enable Service systemd-journal-upload
    ansible.builtin.systemd:
      name: systemd-journal-upload
      enabled: true
      state: started
      masked: false
    when:
    - '"systemd-journal-remote" in ansible_facts.packages'
  when:
  - '"linux-base" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_systemd-journal-upload_enabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include enable_systemd-journal-upload

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

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, Ubuntu 24.04 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
cis6.1.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'systemd-journald.service'
"$SYSTEMCTL_EXEC" start 'systemd-journald.service'
"$SYSTEMCTL_EXEC" enable 'systemd-journald.service'

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


[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: '"linux-base" 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:
cis6.1.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" in ansible_facts.packages'
  tags:
  - journald_compress
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure journald ForwardToSyslog is disabled   [ref]

Data from journald should be kept in the confines of the service and not forwarded to other services.
Rationale:
If journald is the method for capturing logs, all logs of the system should be handled by journald and not forwarded to other logging mechanisms.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_disable_forward_to_syslog
References:
cis6.1.2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { dpkg-query --show --showformat='${db:Status-Status}\n' 'systemd' 2>/dev/null | grep -q installed; }; 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=no" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "ForwardToSyslog=no" >> "/etc/systemd/journald.conf"
    tail -n "+$(( 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_disable_forward_to_syslog
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Setting unquoted shell-style assignment of 'ForwardToSyslog' to 'no' 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=no
      state: present
      insertbefore: ^# ForwardToSyslog
      validate: /usr/bin/bash -n %s
  when:
  - '"linux-base" in ansible_facts.packages'
  - '"systemd" in ansible_facts.packages'
  tags:
  - journald_disable_forward_to_syslog
  - 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:
cis6.1.3.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
cis6.1.2.4

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
cis6.1.2.1.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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
cis6.1.3.7

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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:
  - '"linux-base" 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: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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:
  - '"linux-base" 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:
  - '"linux-base" 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

Rule   Ensure rsyslog is Installed   [ref]

Rsyslog is installed by default. The rsyslog package can be installed with the following command:
 $ apt-get 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
cis6.1.3.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "rsyslog"

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


[[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: '"linux-base" 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   Enable rsyslog Service   [ref]

The rsyslog service provides syslog-style logging by default on Ubuntu 24.04. The rsyslog service can be enabled with the following command:
$ sudo systemctl enable rsyslog.service
Rationale:
The rsyslog service must be running in order to provide logging services, which are essential to system administration.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_rsyslog_enabled
References:
cis-csc1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9
cobit5APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO13.01, BAI03.05, BAI04.04, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01
disaCCI-000366
hipaa164.312(a)(2)(ii)
isa-62443-20094.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4
isa-62443-2013SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, SR 7.1, SR 7.2
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.14.2.7, A.15.2.1, A.15.2.2, A.17.2.1
nistCM-6(a), AU-4(1)
nist-csfDE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.DS-4, PR.PT-1
os-srgSRG-OS-000480-GPOS-00227
cis6.1.3.2

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AU-4(1)
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyslog_enabled

- name: Enable rsyslog Service - Enable service rsyslog
  block:

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

  - name: Enable rsyslog Service - Enable Service rsyslog
    ansible.builtin.systemd:
      name: rsyslog
      enabled: true
      state: started
      masked: false
    when:
    - '"rsyslog" in ansible_facts.packages'
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-AU-4(1)
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyslog_enabled

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

class enable_rsyslog {
  service {'rsyslog':
    enable => true,
    ensure => 'running',
  }
}

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:
cis6.1.3.4

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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:
  - '"linux-base" 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:
  - '"linux-base" 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:
  - '"linux-base" 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 12 groups and 50 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   iptables and ip6tables   Group contains 2 groups and 10 rules
[ref]   A host-based firewall called netfilter is included as part of the Linux kernel distributed with the system. It is activated by default. This firewall is controlled by the program iptables, and the entire capability is frequently referred to by this name. An analogous program called ip6tables handles filtering for IPv6.

Unlike TCP Wrappers, which depends on the network server program to support and respect the rules written, netfilter filtering occurs at the kernel level, before a program can even process the data from the network packet. As such, any program on the system is affected by the rules written.

This section provides basic information about strengthening the iptables and ip6tables configurations included with the system. For more complete information that may allow the construction of a sophisticated ruleset tailored to your environment, please consult the references at the end of this section.
Group   Inspect and Activate Default Rules   Group contains 3 rules
[ref]   View the currently-enforced iptables rules by running the command:
$ sudo iptables -nL --line-numbers
The command is analogous for ip6tables.

If the firewall does not appear to be active (i.e., no rules appear), activate it and ensure that it starts at boot by issuing the following commands (and analogously for ip6tables):
$ sudo service iptables restart
The default iptables rules are:
Chain INPUT (policy ACCEPT)
num  target     prot opt source       destination
1    ACCEPT     all  --  0.0.0.0/0    0.0.0.0/0    state RELATED,ESTABLISHED 
2    ACCEPT     icmp --  0.0.0.0/0    0.0.0.0/0
3    ACCEPT     all  --  0.0.0.0/0    0.0.0.0/0
4    ACCEPT     tcp  --  0.0.0.0/0    0.0.0.0/0    state NEW tcp dpt:22 
5    REJECT     all  --  0.0.0.0/0    0.0.0.0/0    reject-with icmp-host-prohibited 

Chain FORWARD (policy ACCEPT)
num  target     prot opt source       destination
1    REJECT     all  --  0.0.0.0/0    0.0.0.0/0    reject-with icmp-host-prohibited 

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source       destination
The ip6tables default rules are essentially the same.

Rule   Set Default ip6tables Policy for Incoming Packets   [ref]

To set the default policy to DROP (instead of ACCEPT) for the built-in INPUT chain which processes incoming packets, add or correct the following line in /etc/iptables/rules.v6:
:INPUT DROP [0:0]
If changes were required, reload the ip6tables rules:
$ sudo service ip6tables reload
Rationale:
In ip6tables, the default policy is applied only after all the applicable rules in the table are examined for a match. Setting the default policy to DROP implements proper design for a firewall, i.e. any packets which are not explicitly permitted should not be accepted.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_ip6tables_default_rule
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
nerc-cipCIP-003-8 R4, CIP-003-8 R5, CIP-004-6 R3
nistAC-4, CM-7(b), CA-3(5), SC-7(21), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis4.4.3.1
pcidss41.4.1, 1.4

# Remediation is applicable only in certain platforms
if ( ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed ) && ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed ) && dpkg-query --show --showformat='${db:Status-Status}\n' 'iptables' 2>/dev/null | grep -q installed ); then

DEBIAN_FRONTEND=noninteractive apt-get install -y "iptables-persistent"
sed -i 's/^:INPUT ACCEPT.*/:INPUT DROP [0:0]/g' /etc/iptables/rules.v6

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

Rule   Set configuration for IPv6 loopback traffic   [ref]

Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
Loopback traffic is generated between processes on machine and is typically critical to operation of the system. The loopback interface is the only place that loopback network traffic should be seen, all other interfaces should ignore traffic on this network as an anti-spoofing measure.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_ipv6_loopback_traffic
References:
pcidssReq-1.3
cis4.4.3.2
pcidss41.4.1, 1.4

# Remediation is applicable only in certain platforms
if ( ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed ) && ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed ) && dpkg-query --show --showformat='${db:Status-Status}\n' 'iptables' 2>/dev/null | grep -q installed ); then

if [ "$(sysctl -n net.ipv6.conf.all.disable_ipv6)" -eq 0 ]; then
  # IPv6 is not disabled, so run the script
  ip6tables -A INPUT -i lo -j ACCEPT
  ip6tables -A OUTPUT -o lo -j ACCEPT
  ip6tables -A INPUT -s ::1 -j DROP
fi

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

- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_ipv6_loopback_traffic

- name: Check if IPv6 is enabled
  command: sysctl -n net.ipv6.conf.all.disable_ipv6
  register: ipv6_status
  failed_when: ipv6_status.stdout != "0"
  when: ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_ipv6_loopback_traffic

- name: Allow incoming traffic on the loopback interface
  ansible.builtin.iptables:
    ipv6: true
    chain: INPUT
    in_interface: lo
    jump: ACCEPT
  when:
  - ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  - ipv6_status.stdout == '0'
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_ipv6_loopback_traffic

- name: Allow outgoing traffic on the loopback interface
  ansible.builtin.iptables:
    ipv6: true
    chain: OUTPUT
    out_interface: lo
    jump: ACCEPT
  when:
  - ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  - ipv6_status.stdout == '0'
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_ipv6_loopback_traffic

- name: Drop incoming traffic from the localhost
  ansible.builtin.iptables:
    ipv6: true
    chain: INPUT
    source: ::1
    jump: DROP
  when:
  - ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  - ipv6_status.stdout == '0'
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_ipv6_loopback_traffic

Rule   Set configuration for loopback traffic   [ref]

Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
Loopback traffic is generated between processes on machine and is typically critical to operation of the system. The loopback interface is the only place that loopback network traffic should be seen, all other interfaces should ignore traffic on this network as an anti-spoofing measure.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_loopback_traffic
References:
pcidssReq-1.3
cis4.4.2.2
pcidss41.4.1, 1.4

# Remediation is applicable only in certain platforms
if ( ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed ) && ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed ) && dpkg-query --show --showformat='${db:Status-Status}\n' 'iptables' 2>/dev/null | grep -q installed ); then

iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT
iptables -A INPUT -s 127.0.0.0/8 -j DROP

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

- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_loopback_traffic

- name: Allow incoming traffic on the loopback interface
  ansible.builtin.iptables:
    chain: INPUT
    in_interface: lo
    jump: ACCEPT
  when: ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_loopback_traffic

- name: Allow outgoing traffic on the loopback interface
  ansible.builtin.iptables:
    chain: OUTPUT
    out_interface: lo
    jump: ACCEPT
  when: ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_loopback_traffic

- name: Drop incoming traffic from the localhost
  ansible.builtin.iptables:
    chain: INPUT
    source: 127.0.0.0/8
    jump: DROP
  when: ( not ( "nftables" in ansible_facts.packages ) and not ( "ufw" in ansible_facts.packages
    ) and "iptables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.3
  - PCI-DSSv4-1.4
  - PCI-DSSv4-1.4.1
  - medium_severity
  - set_loopback_traffic
Group   Strengthen the Default Ruleset   Group contains 3 rules
[ref]   The default rules can be strengthened. The system scripts that activate the firewall rules expect them to be defined in the configuration files iptables and ip6tables in the directory /etc/sysconfig. Many of the lines in these files are similar to the command line arguments that would be provided to the programs /sbin/iptables or /sbin/ip6tables - but some are quite different.

The following recommendations describe how to strengthen the default ruleset configuration file. An alternative to editing this configuration file is to create a shell script that makes calls to the iptables program to load in rules, and then invokes service iptables save to write those loaded rules to /etc/sysconfig/iptables.

The following alterations can be made directly to /etc/sysconfig/iptables and /etc/sysconfig/ip6tables. Instructions apply to both unless otherwise noted. Language and address conventions for regular iptables are used throughout this section; configuration for ip6tables will be either analogous or explicitly covered.
Warning:  The program system-config-securitylevel allows additional services to penetrate the default firewall rules and automatically adjusts /etc/sysconfig/iptables. This program is only useful if the default ruleset meets your security requirements. Otherwise, this program should not be used to make changes to the firewall configuration because it re-writes the saved configuration file.

Rule   Ensure ip6tables Firewall Rules Exist for All Open Ports   [ref]

Any ports that have been opened on non-loopback addresses need firewall rules to govern traffic.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
Without a firewall rule configured for open ports default firewall policy will drop all packets to these ports.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ip6tables_rules_for_open_ports
References:
cis4.4.3.4

Rule   Ensure iptables Firewall Rules Exist for All Open Ports   [ref]

Any ports that have been opened on non-loopback addresses need firewall rules to govern traffic.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
Without a firewall rule configured for open ports default firewall policy will drop all packets to these ports.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_iptables_rules_for_open_ports
References:
cis4.4.2.4

Rule   Set Default iptables Policy for Incoming Packets   [ref]

To set the default policy to DROP (instead of ACCEPT) for the built-in INPUT chain which processes incoming packets, add or correct the following line in /etc/sysconfig/iptables:
:INPUT DROP [0:0]
Rationale:
In iptables the default policy is applied only after all the applicable rules in the table are examined for a match. Setting the default policy to DROP implements proper design for a firewall, i.e. any packets which are not explicitly permitted should not be accepted.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_iptables_default_rule
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
nistCA-3(5), CM-7(b), SC-7(23), CM-6(a)
nist-csfPR.IP-1, PR.PT-3
cis4.4.2.1

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'iptables' 2>/dev/null | grep -q installed && { ( ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed ) && ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed ) ); }; then

sed -i 's/^:INPUT ACCEPT.*/:INPUT DROP [0:0]/g' /etc/sysconfig/iptables

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

Rule   Install iptables-persistent Package   [ref]

The iptables-persistent package can be installed with the following command:
$ apt-get install iptables-persistent
Rationale:
A method of configuring and maintaining firewall rules is necessary to configure a Host Based Firewall.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_iptables-persistent_installed
References:
cis4.4.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'iptables' 2>/dev/null | grep -q installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "iptables-persistent"

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


[[packages]]
name = "iptables-persistent"
version = "*"

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_iptables-persistent_installed

- name: Ensure iptables-persistent is installed
  package:
    name: iptables-persistent
    state: present
  when: '"iptables" in ansible_facts.packages'
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_iptables-persistent_installed

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include install_iptables-persistent

class install_iptables-persistent {
  package { 'iptables-persistent':
    ensure => 'installed',
  }
}

Rule   Install iptables Package   [ref]

The iptables package can be installed with the following command:
$ apt-get install iptables
Rationale:
iptables controls the Linux kernel network packet filtering code. iptables allows system operators to set up firewalls and IP masquerading, etc.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_iptables_installed
References:
nistCM-6(a)
pcidssReq-1.4.1
os-srgSRG-OS-000480-GPOS-00227
cis4.4.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

DEBIAN_FRONTEND=noninteractive apt-get install -y "iptables"

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


[[packages]]
name = "iptables"
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-DSS-Req-1.4.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_iptables_installed

- name: Ensure iptables is installed
  package:
    name: iptables
    state: present
  when: ( "linux-base" in ansible_facts.packages )
  tags:
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-1.4.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_iptables_installed

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

class install_iptables {
  package { 'iptables':
    ensure => 'installed',
  }
}

Rule   Remove iptables-persistent Package   [ref]

The iptables-persistent package can be removed with the following command:
$ apt-get remove iptables-persistent
Rationale:
Running both ufw and the services included in the iptables-persistent package may lead to conflict.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_iptables-persistent_removed
References:
cis4.2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed; then

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "iptables-persistent"

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
  - package_iptables-persistent_removed

- name: Ensure iptables-persistent is removed
  package:
    name: iptables-persistent
    state: absent
  when: '"ufw" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_iptables-persistent_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_iptables-persistent

class remove_iptables-persistent {
  package { 'iptables-persistent':
    ensure => 'purged',
  }
}

Rule   Ensure iptables are flushed   [ref]

nftables is a replacement for iptables, ip6tables, ebtables and arptables
Rationale:
It is possible to mix iptables and nftables. However, this increases complexity and also the chance to introduce errors. For simplicity flush out all iptables rules, and ensure it is not loaded.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ensure_iptables_are_flushed
References:
cis4.3.3
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
cis3.3.11

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.all.accept_ra from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.all.accept_ra.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.all.accept_ra" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_all_accept_ra_value='0'


#
# Set runtime for net.ipv6.conf.all.accept_ra
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.all.accept_ra="$sysctl_net_ipv6_conf_all_accept_ra_value"
fi

#
# If net.ipv6.conf.all.accept_ra present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.all.accept_ra = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.all.accept_ra")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_all_accept_ra_value"

# 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 "^net.ipv6.conf.all.accept_ra\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.all.accept_ra\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.all.accept_ra.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.5

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.all.accept_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.all.accept_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.all.accept_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_all_accept_redirects_value='0'


#
# Set runtime for net.ipv6.conf.all.accept_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.all.accept_redirects="$sysctl_net_ipv6_conf_all_accept_redirects_value"
fi

#
# If net.ipv6.conf.all.accept_redirects present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.all.accept_redirects = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.all.accept_redirects")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_all_accept_redirects_value"

# 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 "^net.ipv6.conf.all.accept_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.all.accept_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.all.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.8

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.all.accept_source_route from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.all.accept_source_route.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.all.accept_source_route" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_all_accept_source_route_value='0'


#
# Set runtime for net.ipv6.conf.all.accept_source_route
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.all.accept_source_route="$sysctl_net_ipv6_conf_all_accept_source_route_value"
fi

#
# If net.ipv6.conf.all.accept_source_route present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.all.accept_source_route = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.all.accept_source_route")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_all_accept_source_route_value"

# 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 "^net.ipv6.conf.all.accept_source_route\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.all.accept_source_route\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.all.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.all.forwarding from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.all.forwarding.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.all.forwarding" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_all_forwarding_value='0'


#
# Set runtime for net.ipv6.conf.all.forwarding
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.all.forwarding="$sysctl_net_ipv6_conf_all_forwarding_value"
fi

#
# If net.ipv6.conf.all.forwarding present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.all.forwarding = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.all.forwarding")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_all_forwarding_value"

# 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 "^net.ipv6.conf.all.forwarding\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.all.forwarding\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.all.forwarding.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.11

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.default.accept_ra from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.default.accept_ra.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.default.accept_ra" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_default_accept_ra_value='0'


#
# Set runtime for net.ipv6.conf.default.accept_ra
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.default.accept_ra="$sysctl_net_ipv6_conf_default_accept_ra_value"
fi

#
# If net.ipv6.conf.default.accept_ra present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.default.accept_ra = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.default.accept_ra")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_default_accept_ra_value"

# 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 "^net.ipv6.conf.default.accept_ra\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.default.accept_ra\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.default.accept_ra.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.5

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.default.accept_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.default.accept_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.default.accept_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_default_accept_redirects_value='0'


#
# Set runtime for net.ipv6.conf.default.accept_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.default.accept_redirects="$sysctl_net_ipv6_conf_default_accept_redirects_value"
fi

#
# If net.ipv6.conf.default.accept_redirects present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.default.accept_redirects = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.default.accept_redirects")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_default_accept_redirects_value"

# 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 "^net.ipv6.conf.default.accept_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.default.accept_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.default.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.8
pcidss41.4.2, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv6.conf.default.accept_source_route from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.default.accept_source_route.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.default.accept_source_route" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv6_conf_default_accept_source_route_value='0'


#
# Set runtime for net.ipv6.conf.default.accept_source_route
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv6.conf.default.accept_source_route="$sysctl_net_ipv6_conf_default_accept_source_route_value"
fi

#
# If net.ipv6.conf.default.accept_source_route present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.default.accept_source_route = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.default.accept_source_route")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_default_accept_source_route_value"

# 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 "^net.ipv6.conf.default.accept_source_route\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv6.conf.default.accept_source_route\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv6.conf.default.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.5

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.all.accept_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.all.accept_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.all.accept_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_all_accept_redirects_value='0'


#
# Set runtime for net.ipv4.conf.all.accept_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.all.accept_redirects="$sysctl_net_ipv4_conf_all_accept_redirects_value"
fi

#
# If net.ipv4.conf.all.accept_redirects present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.all.accept_redirects = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.all.accept_redirects")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_all_accept_redirects_value"

# 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 "^net.ipv4.conf.all.accept_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.all.accept_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.all.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.8

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.all.accept_source_route from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.all.accept_source_route.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.all.accept_source_route" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_all_accept_source_route_value='0'


#
# Set runtime for net.ipv4.conf.all.accept_source_route
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.all.accept_source_route="$sysctl_net_ipv4_conf_all_accept_source_route_value"
fi

#
# If net.ipv4.conf.all.accept_source_route present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.all.accept_source_route = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.all.accept_source_route")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_all_accept_source_route_value"

# 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 "^net.ipv4.conf.all.accept_source_route\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.all.accept_source_route\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.all.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.9

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.all.log_martians from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.all.log_martians.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.all.log_martians" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_all_log_martians_value='1'


#
# Set runtime for net.ipv4.conf.all.log_martians
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.all.log_martians="$sysctl_net_ipv4_conf_all_log_martians_value"
fi

#
# If net.ipv4.conf.all.log_martians present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.all.log_martians = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.all.log_martians")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_all_log_martians_value"

# 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 "^net.ipv4.conf.all.log_martians\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.all.log_martians\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.all.log_martians.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.all.rp_filter from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.all.rp_filter.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.all.rp_filter" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_all_rp_filter_value='1'


#
# Set runtime for net.ipv4.conf.all.rp_filter
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.all.rp_filter="$sysctl_net_ipv4_conf_all_rp_filter_value"
fi

#
# If net.ipv4.conf.all.rp_filter present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.all.rp_filter = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.all.rp_filter")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_all_rp_filter_value"

# 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 "^net.ipv4.conf.all.rp_filter\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.all.rp_filter\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.all.rp_filter.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.6
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.all.secure_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.all.secure_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.all.secure_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_all_secure_redirects_value='0'


#
# Set runtime for net.ipv4.conf.all.secure_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.all.secure_redirects="$sysctl_net_ipv4_conf_all_secure_redirects_value"
fi

#
# If net.ipv4.conf.all.secure_redirects present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.all.secure_redirects = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.all.secure_redirects")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_all_secure_redirects_value"

# 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 "^net.ipv4.conf.all.secure_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.all.secure_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.all.secure_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.5
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.default.accept_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.default.accept_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.default.accept_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_default_accept_redirects_value='0'


#
# Set runtime for net.ipv4.conf.default.accept_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.default.accept_redirects="$sysctl_net_ipv4_conf_default_accept_redirects_value"
fi

#
# If net.ipv4.conf.default.accept_redirects present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.default.accept_redirects = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.default.accept_redirects")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_default_accept_redirects_value"

# 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 "^net.ipv4.conf.default.accept_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.default.accept_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.default.accept_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.8

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.default.accept_source_route from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.default.accept_source_route.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.default.accept_source_route" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_default_accept_source_route_value='0'


#
# Set runtime for net.ipv4.conf.default.accept_source_route
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.default.accept_source_route="$sysctl_net_ipv4_conf_default_accept_source_route_value"
fi

#
# If net.ipv4.conf.default.accept_source_route present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.default.accept_source_route = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.default.accept_source_route")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_default_accept_source_route_value"

# 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 "^net.ipv4.conf.default.accept_source_route\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.default.accept_source_route\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.default.accept_source_route.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.9

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.default.log_martians from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.default.log_martians.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.default.log_martians" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_default_log_martians_value='1'


#
# Set runtime for net.ipv4.conf.default.log_martians
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.default.log_martians="$sysctl_net_ipv4_conf_default_log_martians_value"
fi

#
# If net.ipv4.conf.default.log_martians present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.default.log_martians = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.default.log_martians")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_default_log_martians_value"

# 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 "^net.ipv4.conf.default.log_martians\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.default.log_martians\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.default.log_martians.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.default.rp_filter from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.default.rp_filter.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.default.rp_filter" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_default_rp_filter_value='1'


#
# Set runtime for net.ipv4.conf.default.rp_filter
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.default.rp_filter="$sysctl_net_ipv4_conf_default_rp_filter_value"
fi

#
# If net.ipv4.conf.default.rp_filter present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.default.rp_filter = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.default.rp_filter")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_default_rp_filter_value"

# 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 "^net.ipv4.conf.default.rp_filter\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.default.rp_filter\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.default.rp_filter.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.6

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.default.secure_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.default.secure_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.default.secure_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_conf_default_secure_redirects_value='0'


#
# Set runtime for net.ipv4.conf.default.secure_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.default.secure_redirects="$sysctl_net_ipv4_conf_default_secure_redirects_value"
fi

#
# If net.ipv4.conf.default.secure_redirects present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.conf.default.secure_redirects = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.default.secure_redirects")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_conf_default_secure_redirects_value"

# 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 "^net.ipv4.conf.default.secure_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.default.secure_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.default.secure_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.4
pcidss41.4.2, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.icmp_echo_ignore_broadcasts from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.icmp_echo_ignore_broadcasts.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.icmp_echo_ignore_broadcasts" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_icmp_echo_ignore_broadcasts_value='1'


#
# Set runtime for net.ipv4.icmp_echo_ignore_broadcasts
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.icmp_echo_ignore_broadcasts="$sysctl_net_ipv4_icmp_echo_ignore_broadcasts_value"
fi

#
# If net.ipv4.icmp_echo_ignore_broadcasts present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.icmp_echo_ignore_broadcasts = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.icmp_echo_ignore_broadcasts")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_icmp_echo_ignore_broadcasts_value"

# 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 "^net.ipv4.icmp_echo_ignore_broadcasts\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.icmp_echo_ignore_broadcasts\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.icmp_echo_ignore_broadcasts.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.3
pcidss41.4.2, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.icmp_ignore_bogus_error_responses from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.icmp_ignore_bogus_error_responses.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.icmp_ignore_bogus_error_responses" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_icmp_ignore_bogus_error_responses_value='1'


#
# Set runtime for net.ipv4.icmp_ignore_bogus_error_responses
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.icmp_ignore_bogus_error_responses="$sysctl_net_ipv4_icmp_ignore_bogus_error_responses_value"
fi

#
# If net.ipv4.icmp_ignore_bogus_error_responses present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.icmp_ignore_bogus_error_responses = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.icmp_ignore_bogus_error_responses")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_icmp_ignore_bogus_error_responses_value"

# 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 "^net.ipv4.icmp_ignore_bogus_error_responses\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.icmp_ignore_bogus_error_responses\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.icmp_ignore_bogus_error_responses.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.10
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.tcp_syncookies from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.tcp_syncookies.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.tcp_syncookies" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_net_ipv4_tcp_syncookies_value='1'


#
# Set runtime for net.ipv4.tcp_syncookies
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.tcp_syncookies="$sysctl_net_ipv4_tcp_syncookies_value"
fi

#
# If net.ipv4.tcp_syncookies present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv4.tcp_syncookies = value" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.tcp_syncookies")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv4_tcp_syncookies_value"

# 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 "^net.ipv4.tcp_syncookies\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.tcp_syncookies\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.tcp_syncookies.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.2
pcidss41.4.5, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.all.send_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.all.send_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.all.send_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for net.ipv4.conf.all.send_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.all.send_redirects="0"
fi

#
# If net.ipv4.conf.all.send_redirects present in /etc/sysctl.conf, change value to "0"
#	else, add "net.ipv4.conf.all.send_redirects = 0" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.all.send_redirects")

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

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^net.ipv4.conf.all.send_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.all.send_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.all.send_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.2
pcidss41.4.5, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.conf.default.send_redirects from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.conf.default.send_redirects.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.conf.default.send_redirects" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for net.ipv4.conf.default.send_redirects
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.conf.default.send_redirects="0"
fi

#
# If net.ipv4.conf.default.send_redirects present in /etc/sysctl.conf, change value to "0"
#	else, add "net.ipv4.conf.default.send_redirects = 0" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.conf.default.send_redirects")

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

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^net.ipv4.conf.default.send_redirects\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.conf.default.send_redirects\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.conf.default.send_redirects.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
cis3.3.1
pcidss41.4.3, 1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

# Comment out any occurrences of net.ipv4.ip_forward from /etc/sysctl.d/*.conf files

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


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

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv4.ip_forward.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv4.ip_forward" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

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

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for net.ipv4.ip_forward
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w net.ipv4.ip_forward="0"
fi

#
# If net.ipv4.ip_forward present in /etc/sysctl.conf, change value to "0"
#	else, add "net.ipv4.ip_forward = 0" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv4.ip_forward")

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

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^net.ipv4.ip_forward\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^net.ipv4.ip_forward\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

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

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/
    contains: ^[\s]*net.ipv4.ip_forward.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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   nftables   Group contains 8 rules
[ref]   If firewalld or iptables are being used in your environment, please follow the guidance in their respective section and pass-over the guidance in this section.

nftables is a subsystem of the Linux kernel providing filtering and classification of network packets/datagrams/frames and is the successor to iptables. The biggest change with the successor nftables is its simplicity. With iptables, we have to configure every single rule and use the syntax which can be compared with normal commands. With nftables, the simpler syntax, much like BPF (Berkely Packet Filter) means shorter lines and less repetition. Support for nftables should also be compiled into the kernel, together with the related nftables modules.

It is available in Linux kernels >= 3.13. Please ensure that your kernel supports nftables before choosing this option.

Rule   Install nftables Package   [ref]

nftables provides a new in-kernel packet classification framework that is based on a network-specific Virtual Machine (VM) and a new nft userspace command line tool. nftables reuses the existing Netfilter subsystems such as the existing hook infrastructure, the connection tracking system, NAT, userspace queuing and logging subsystem. The nftables package can be installed with the following command:
$ apt-get install nftables
Rationale:
nftables is a subsystem of the Linux kernel that can protect against threats originating from within a corporate network to include malicious mobile code and poorly configured software on a host.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_nftables_installed
References:
cis4.3.1
pcidss41.2.1, 1.2

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

DEBIAN_FRONTEND=noninteractive apt-get install -y "nftables"

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_nftables_installed

- name: Ensure nftables is installed
  package:
    name: nftables
    state: present
  when: ( "linux-base" in ansible_facts.packages )
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_nftables_installed

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

class install_nftables {
  package { 'nftables':
    ensure => 'installed',
  }
}

Rule   Uninstall nftables package   [ref]

nftables is a subsystem of the Linux kernel providing filtering and classification of network packets/datagrams/frames and is the successor to iptables. The nftables package can be removed with the following command:
$ apt-get remove nftables
Rationale:
Running both firewalld and nftables may lead to conflict.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_nftables_removed
References:
cis4.4.1.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "nftables"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure nftables is removed
  package:
    name: nftables
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_nftables_removed

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

class remove_nftables {
  package { 'nftables':
    ensure => 'purged',
  }
}

Rule   Verify nftables Service is Enabled   [ref]

The nftables service allows for the loading of nftables rulesets during boot, or starting on the nftables service The nftables service can be enabled with the following command:
$ sudo systemctl enable nftables.service
Rationale:
The nftables service restores the nftables rules from the rules files referenced in the /etc/sysconfig/nftables.conf file during boot or the starting of the nftables service
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_nftables_enabled
References:
cis4.3.9

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_enabled

- name: Verify nftables Service is Enabled - Enable service nftables
  block:

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

  - name: Verify nftables Service is Enabled - Enable Service nftables
    ansible.builtin.systemd:
      name: nftables
      enabled: true
      state: started
      masked: false
    when:
    - '"nftables" in ansible_facts.packages'
  when: ( "nftables" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_enabled

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

class enable_nftables {
  service {'nftables':
    enable => true,
    ensure => 'running',
  }
}

Rule   Verify nftables Service is Disabled   [ref]

nftables is a subsystem of the Linux kernel providing filtering and classification of network packets/datagrams/frames and is the successor to iptables. The nftables service can be disabled with the following command:
systemctl disable nftables
Rationale:
Running both firewalld and nftables may lead to conflict. nftables is actually one of the backends for firewalld management tools.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_nftables_disabled
References:
cis4.4.1.2
pcidss41.2.1, 1.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'firewalld' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_disabled

- name: Verify nftables Service is Disabled - 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: ( "firewalld" in ansible_facts.packages and "nftables" in ansible_facts.packages
    and "linux-base" in ansible_facts.packages )
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_disabled

- name: Verify nftables Service is Disabled - Ensure nftables.service is Masked
  ansible.builtin.systemd:
    name: nftables.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( "firewalld" in ansible_facts.packages and "nftables" in ansible_facts.packages
    and "linux-base" in ansible_facts.packages )
  - service_exists.stdout_lines is search("nftables.service", multiline=True)
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_disabled

- name: Unit Socket Exists - nftables.socket
  ansible.builtin.command: systemctl -q list-unit-files nftables.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( "firewalld" in ansible_facts.packages and "nftables" in ansible_facts.packages
    and "linux-base" in ansible_facts.packages )
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_disabled

- name: Verify nftables Service is Disabled - Disable Socket nftables
  ansible.builtin.systemd:
    name: nftables.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( "firewalld" in ansible_facts.packages and "nftables" in ansible_facts.packages
    and "linux-base" in ansible_facts.packages )
  - socket_file_exists.stdout_lines is search("nftables.socket", multiline=True)
  tags:
  - PCI-DSSv4-1.2
  - PCI-DSSv4-1.2.1
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_nftables_disabled

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

class disable_nftables {
  service {'nftables':
    enable => false,
    ensure => 'stopped',
  }
}

Rule   Ensure nftables Default Deny Firewall Policy   [ref]

Base chain policy is the default verdict that will be applied to packets reaching the end of the chain. There are two policies: accept (Default) and drop. If the policy is set to accept, the firewall will accept any packet that is not configured to be denied and the packet will continue traversing the network stack. {% if 'ubuntu' in product %} Run the following commands and verify that base chains contain a policy of DROP.
$ nft list ruleset | grep 'hook input'
type filter hook input priority 0; policy drop;
$ nft list ruleset | grep 'hook forward'
type filter hook forward priority 0; policy drop;
$ nft list ruleset | grep 'hook output'
type filter hook output priority 0; policy drop;
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
It is easier to allow acceptable usage than to block unacceptable usage.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_nftables_ensure_default_deny_policy
References:
cis4.3.8
pcidss41.3.1, 1.3

Rule   Ensure Base Chains Exist for Nftables   [ref]

Tables in nftables hold chains. Each table only has one address family and only applies to packets of this family. Tables can have one of six families. Chains are containers for rules. They exist in two kinds, base chains and regular chains. A base chain is an entry point for packets from the networking stack, a regular chain may be used as jump target and is used for better rule organization.
Warning:  Configuring rules over ssh, by creating a base chain with policy drop will cause loss of connectivity. Ensure that a rule allowing ssh has been added to the base chain prior to setting the base cahin's policy to drop
Rationale:
If a base chain doesn't exist with a hook for input, forward, and delete, packets that would flow through those chains will not be touched by nftables.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_nftables_base_chain
References:
cis4.3.5

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed; then

#Name of the table
var_nftables_table='filter'

#Familiy of the table 
var_nftables_family='inet'

#Name(s) of base chain
var_nftables_base_chain_names='input,forward,output'

#Type(s) of base chain
var_nftables_base_chain_types='filter,filter,filter'

# Hooks for base chain
var_nftables_base_chain_hooks='input,forward,output'

#Priority
var_nftables_base_chain_priorities='0,0,0'

#Policy 
var_nftables_base_chain_policies='accept,accept,accept'


#Transfer some of strings to arrays
IFS="," read -r -a  names <<< "$var_nftables_base_chain_names"
IFS="," read -r -a  types <<< "$var_nftables_base_chain_types"
IFS="," read -r -a  hooks <<< "$var_nftables_base_chain_hooks"
IFS="," read -r -a  priorities <<< "$var_nftables_base_chain_priorities"
IFS="," read -r -a  policies <<< "$var_nftables_base_chain_policies"

my_cmd="nft list tables | grep '$var_nftables_family $var_nftables_table'"
eval IS_TABLE_EXIST=\$\($my_cmd\)
if [ -z "$IS_TABLE_EXIST" ]
then
  # We create a table and add chains to it 
  nft create table "$var_nftables_family" "$var_nftables_table"
  num_of_chains=${#names[@]}
  for ((i=0; i < num_of_chains; i++))
  do
   chain_to_add="add chain $var_nftables_family $var_nftables_table ${names[$i]} { type ${types[$i]} hook ${hooks[$i]} priority ${priorities[$i]} ; policy ${policies[$i]} ; }"
   my_cmd="nft '$chain_to_add'"
   eval $my_cmd
  done    
else
  # We add missing chains to the existing table
  num_of_chains=${#names[@]}
  for ((i=0; i < num_of_chains; i++))
  do
    IS_CHAIN_EXIST=$(nft list table "$var_nftables_family" "$var_nftables_table" | grep "hook ${hooks[$i]}")
    if [ -z "$IS_CHAIN_EXIST" ]
      then
        chain_to_add="add chain '$var_nftables_family' '$var_nftables_table' ${names[$i]} { type ${types[$i]} hook ${hooks[$i]} priority ${priorities[$i]} ; policy ${policies[$i]} ; }"
        my_cmd="nft '$chain_to_add'"
        eval $my_cmd
    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:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_base_chain
- name: XCCDF Value var_nftables_table # promote to variable
  set_fact:
    var_nftables_table: !!str filter
  tags:
    - always
- name: XCCDF Value var_nftables_family # promote to variable
  set_fact:
    var_nftables_family: !!str inet
  tags:
    - always
- name: XCCDF Value var_nftables_base_chain_names # promote to variable
  set_fact:
    var_nftables_base_chain_names: !!str input,forward,output
  tags:
    - always
- name: XCCDF Value var_nftables_base_chain_types # promote to variable
  set_fact:
    var_nftables_base_chain_types: !!str filter,filter,filter
  tags:
    - always
- name: XCCDF Value var_nftables_base_chain_hooks # promote to variable
  set_fact:
    var_nftables_base_chain_hooks: !!str input,forward,output
  tags:
    - always
- name: XCCDF Value var_nftables_base_chain_priorities # promote to variable
  set_fact:
    var_nftables_base_chain_priorities: !!str 0,0,0
  tags:
    - always
- name: XCCDF Value var_nftables_base_chain_policies # promote to variable
  set_fact:
    var_nftables_base_chain_policies: !!str accept,accept,accept
  tags:
    - always

- name: Ensure Base Chains Exist for Nftables - Check Existence of Nftables Table
  ansible.builtin.shell: nft list tables | grep '{{ var_nftables_family }} {{ var_nftables_table
    }}'
  register: existing_nftables
  changed_when: false
  failed_when: false
  when: '"nftables" in ansible_facts.packages'
  tags:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_base_chain

- name: Ensure Base Chains Exist for Nftables - Set NFTables Table
  ansible.builtin.command: nft create table {{ var_nftables_family }} {{ var_nftables_table
    }}
  when:
  - '"nftables" in ansible_facts.packages'
  - existing_nftables is not skipped and existing_nftables.rc > 0
  tags:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_base_chain

- name: Ensure Base Chains Exist for Nftables - Add Base Chains
  ansible.builtin.command: nft 'add chain {{ var_nftables_family }} {{ var_nftables_table
    }} {{ item.0 }} { type {{ item.1 }} hook {{ item.2 }} priority {{ item.3 }} ;
    policy {{ item.4 }} ; }'
  with_together:
  - '{{ var_nftables_base_chain_names.split(",") }}'
  - '{{ var_nftables_base_chain_types.split(",") }}'
  - '{{ var_nftables_base_chain_hooks.split(",") }}'
  - '{{ var_nftables_base_chain_priorities.split(",") }}'
  - '{{ var_nftables_base_chain_policies.split(",") }}'
  when: '"nftables" in ansible_facts.packages'
  tags:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_base_chain

Rule   Set nftables Configuration for Loopback Traffic   [ref]

Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system. Keep in mind the remediation makes changes only to the running system, in order to keep the changes need to take care to save the nft settings to the relvant configutation files.
Rationale:
Loopback traffic is generated between processes on machine and is typically critical to operation of the system. The loopback interface is the only place that loopback network traffic should be seen, all other interfaces should ignore traffic on this network as an anti-spoofing measure.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_nftables_loopback_traffic
References:
pcidssReq-1.4.1
cis4.3.6

# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed ); then

var_nftables_family='inet'



grubfile="/boot/grub/grub.cfg"

# Implement the loopback rules:
nft add rule inet filter input iif lo accept
nft add rule inet filter input ip saddr 127.0.0.0/8 counter drop

# Check IPv6 is disabled, if false implement IPv6 loopback rules
disabled="false"
[ -f "$grubfile" ] && ! grep "^\s*linux" "$grubfile" | grep -vq "ipv6.disable=1" && disabled="true"

grep -Eq "^\s*net\.ipv6\.conf\.all\.disable_ipv6\s*=\s*1\b(\s+#.*)?$" \
/etc/sysctl.conf /etc/sysctl.d/*.conf && \
grep -Eq "^\s*net\.ipv6\.conf\.default\.disable_ipv6\s*=\s*1\b(\s+#.*)?$" \
/etc/sysctl.conf /etc/sysctl.d/*.conf && sysctl net.ipv6.conf.all.disable_ipv6 | \
grep -Eq "^\s*net\.ipv6\.conf\.all\.disable_ipv6\s*=\s*1\b(\s+#.*)?$" && \
sysctl net.ipv6.conf.default.disable_ipv6 | \
grep -Eq "^\s*net\.ipv6\.conf\.default\.disable_ipv6\s*=\s*1\b(\s+#.*)?$" && disabled="true"

# Is IPv6 Disabled? (true/false)
if [ "$disabled" = false ] ; then
    nft add rule inet filter input ip6 saddr ::1 counter drop
fi


nft list ruleset > "/etc/${var_nftables_family}-filter.rules"

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-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

- name: Implement Loopback Rules
  ansible.builtin.command: nft add rule inet filter input iif lo accept
  when: ( "nftables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

- name: Create Rule to Drop Input IP Address from Loopback
  ansible.builtin.command: nft add rule inet filter input ip saddr 127.0.0.0/8 counter
    drop
  when: ( "nftables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

- name: Check if IPv6 is Disabled in grub Configuration
  ansible.builtin.shell: |
    [ -z "$(grep "^\s*linux" /boot/grub2/grub.cfg | grep -v ipv6.disabled=1)" ]
  register: ipv6_status
  when: ( "nftables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

- name: Check sysctl value of net.ipv6.conf.all.disable_ipv6
  sysctl:
    name: net.ipv6.conf.all.disable_ipv6
    state: present
    value: '1'
  check_mode: true
  register: sysctl_ipv6_all
  when: ( "nftables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

- name: Check sysctl value of net.ipv6.conf.default.disable_ipv6
  sysctl:
    name: net.ipv6.conf.default.disable_ipv6
    state: present
    value: '1'
  check_mode: true
  register: sysctl_ipv6_default
  when: ( "nftables" in ansible_facts.packages )
  tags:
  - PCI-DSS-Req-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

- name: Implement IPv6 loopback rules
  ansible.builtin.command: nft add rule inet filter input ip6 saddr ::1 counter drop
  when:
  - ( "nftables" in ansible_facts.packages )
  - ipv6_status is not skipped
  - sysctl_ipv6_default is not skipped
  - sysctl_ipv6_all is not skipped
  - ipv6_status.rc == 0 or sysctl_ipv6_all.found > 0 or sysctl_ipv6_default.found
    > 0
  tags:
  - PCI-DSS-Req-1.4.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_loopback_traffic

Rule   Ensure a Table Exists for Nftables   [ref]

Tables in nftables hold chains. Each table only has one address family and only applies to packets of this family. Tables can have one of six families.
Warning:  Adding or editing rules in a running nftables can cause loss of connectivity to the system.
Warning:  Both the SCE check and remediation for this rule only consider runtime settings. There is no specific file to check as it depends on each site's policy. Therefore, check and remediation use the nft command directly. The fix is not persistent across system reboots.
Warning:  SCE check does not support variables, therefore the SCE check in this rule only checks the address family, regardless of the table name.
Rationale:
Nftables doesn't have any default tables. Without a table being built, nftables will not filter network traffic.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_nftables_table
References:
cis4.3.4

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'nftables' 2>/dev/null | grep -q installed; then

var_nftables_family='inet'

var_nftables_table='filter'


if ! nft list table $var_nftables_family $var_nftables_table; then
  nft create table "$var_nftables_family" "$var_nftables_table"
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:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_table
- name: XCCDF Value var_nftables_family # promote to variable
  set_fact:
    var_nftables_family: !!str inet
  tags:
    - always
- name: XCCDF Value var_nftables_table # promote to variable
  set_fact:
    var_nftables_table: !!str filter
  tags:
    - always

- name: Collect Existing Nftables
  ansible.builtin.command: nft list table {{ var_nftables_family }} {{ var_nftables_table
    }}
  register: result_nftables_table_family
  changed_when: false
  failed_when: result_nftables_table_family.rc not in [0, 1]
  when: '"nftables" in ansible_facts.packages'
  tags:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_table

- name: Set Nftable Table
  ansible.builtin.command: nft create table {{ var_nftables_family }} {{ var_nftables_table
    }}
  when:
  - '"nftables" in ansible_facts.packages'
  - result_nftables_table_family is not skipped
  - result_nftables_table_family.rc != 0
  tags:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - set_nftables_table
Group   Uncomplicated Firewall (ufw)   Group contains 7 rules
[ref]   The Linux kernel in Ubuntu provides a packet filtering system called netfilter, and the traditional interface for manipulating netfilter are the iptables suite of commands. iptables provide a complete firewall solution that is both highly configurable and highly flexible. Becoming proficient in iptables takes time, and getting started with netfilter firewalling using only iptables can be a daunting task. As a result, many frontends for iptables have been created over the years, each trying to achieve a different result and targeting a different audience. The Uncomplicated Firewall (ufw) is a frontend for iptables and is particularly well-suited for host-based firewalls. ufw provides a framework for managing netfilter, as well as a command-line interface for manipulating the firewall. ufw aims to provide an easy to use interface for people unfamiliar with firewall concepts, while at the same time simplifies complicated iptables commands to help an administrator who knows what he or she is doing. ufw is an upstream for other distributions and graphical frontends.

Rule   Install ufw Package   [ref]

The ufw package can be installed with the following command:
$ apt-get install ufw
Rationale:
ufw controls the Linux kernel network packet filtering code. ufw allows system operators to set up firewalls and IP masquerading, etc.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_ufw_installed
References:
disaCCI-002314
os-srgSRG-OS-000297-GPOS-00115
cis4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "ufw"

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_ufw_installed

- name: Ensure ufw is installed
  package:
    name: ufw
    state: present
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_ufw_installed

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

class install_ufw {
  package { 'ufw':
    ensure => 'installed',
  }
}

Rule   Remove ufw Package   [ref]

The ufw package can be removed with the following command:
$ apt-get remove ufw
Rationale:
Running iptables.persistent with ufw enabled may lead to conflict and unexpected results.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_ufw_removed
References:
cis4.3.2, 4.4.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "ufw"

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
  - package_ufw_removed

- name: Ensure ufw is removed
  package:
    name: ufw
    state: absent
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_ufw_removed

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

class remove_ufw {
  package { 'ufw':
    ensure => 'purged',
  }
}

Rule   Verify ufw Enabled   [ref]

The ufw service can be enabled with the following command:
$ sudo systemctl enable ufw.service
Rationale:
The ufw service must be enabled and running in order for ufw to protect the system
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_ufw_enabled
References:
disaCCI-002314
os-srgSRG-OS-000297-GPOS-00115
cis4.2.3

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); }; then

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ufw_enabled

- name: Verify ufw Enabled - Enable service ufw
  block:

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

  - name: Verify ufw Enabled - Enable Service ufw
    ansible.builtin.systemd:
      name: ufw
      enabled: true
      state: started
      masked: false
    when:
    - '"ufw" in ansible_facts.packages'
  when:
  - '"linux-base" in ansible_facts.packages'
  - ( "ufw" in ansible_facts.packages and "linux-base" in ansible_facts.packages )
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ufw_enabled

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

class enable_ufw {
  service {'ufw':
    enable => true,
    ensure => 'running',
  }
}

Rule   Verify ufw Active   [ref]

Verify the ufw is enabled on the system with the following command:
# sudo ufw status
If the above command returns the status as "inactive" or any type of error, this is a finding.
Rationale:
Remote access services, such as those providing remote access to network devices and information systems, which lack automated control capabilities, increase risk and make remote user access management difficult at best. Remote access is access to DOD nonpublic information systems by an authorized user (or an information system) communicating through an external, nonorganization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Ubuntu 22.04 LTS functionality (e.g., RDP) must be capable of taking enforcement action if the audit reveals unauthorized activity. Automated control of remote access sessions allows organizations to ensure ongoing compliance with remote access policies by enforcing connection rules of remote access applications on a variety of information system components.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_check_ufw_active
References:
disaCCI-002314
cis4.2.3

Rule   Ensure ufw Default Deny Firewall Policy   [ref]

A default deny policy on connections ensures that any unconfigured network usage will be rejected. Note: Any port or protocol without a explicit allow before the default deny will be blocked.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
With a default accept policy the firewall will accept any packet that is not configured to be denied. It is easier to allow acceptable usage than to block unacceptable usage.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_ufw_default_rule
References:
cis4.2.7

Rule   Set UFW Loopback Traffic   [ref]

Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
Loopback traffic is generated between processes on machine and is typically critical to operation of the system. The loopback interface is the only place that loopback network traffic should be seen, all other interfaces should ignore traffic on this network as an anti-spoofing measure.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_ufw_loopback_traffic
References:
cis4.2.4

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { dpkg-query --show --showformat='${db:Status-Status}\n' 'ufw' 2>/dev/null | grep -q installed; }; then

ufw allow in on lo
ufw allow out on lo
ufw deny in from 127.0.0.0/8
ufw deny in from ::1

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

Rule   Ensure ufw Firewall Rules Exist for All Open Ports   [ref]

Any ports that have been opened on non-loopback addresses need firewall rules to govern traffic.
Warning:  Changing firewall settings while connected over network can result in being locked out of the system.
Rationale:
Without a firewall rule configured for open ports default firewall policy will drop all packets to these ports.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_ufw_rules_for_open_ports
References:
cis4.2.6
Group   Wireless Networking   Group contains 1 group and 2 rules
[ref]   Wireless networking, such as 802.11 (WiFi) and Bluetooth, can present a security risk to sensitive or classified systems and networks. Wireless networking hardware is much more likely to be included in laptop or portable systems than in desktops or servers.

Removal of hardware provides the greatest assurance that the wireless capability remains disabled. Acquisition policies often include provisions to prevent the purchase of equipment that will be used in sensitive spaces and includes wireless capabilities. If it is impractical to remove the wireless hardware, and policy permits the device to enter sensitive spaces as long as wireless is disabled, efforts should instead focus on disabling wireless capability via software.
Group   Disable Wireless Through Software Configuration   Group contains 2 rules
[ref]   If it is impossible to remove the wireless hardware from the device in question, disable as much of it as possible through software. The following methods can disable software support for wireless networking, but note that these methods do not prevent malicious software or careless users from re-activating the devices.

Rule   Disable Bluetooth Service   [ref]

The bluetooth service can be disabled with the following command:
$ sudo systemctl mask --now bluetooth.service
$ sudo service bluetooth stop
Rationale:
Disabling the bluetooth service prevents the system from attempting connections to Bluetooth devices, which entails some security risk. Nevertheless, variation in this risk decision may be expected due to the utility of Bluetooth connectivity and its limited range.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_bluetooth_disabled
References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
cui3.1.16
disaCCI-000085, CCI-001551
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
nistAC-18(a), AC-18(3), CM-7(a), CM-7(b), CM-6(a), MP-7
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
cis3.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_bluetooth_disabled

- name: Disable Bluetooth 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: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_bluetooth_disabled

- name: Disable Bluetooth Service - Ensure bluetooth.service is Masked
  ansible.builtin.systemd:
    name: bluetooth.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("bluetooth.service", multiline=True)
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_bluetooth_disabled

- name: Unit Socket Exists - bluetooth.socket
  ansible.builtin.command: systemctl -q list-unit-files bluetooth.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_bluetooth_disabled

- name: Disable Bluetooth Service - Disable Socket bluetooth
  ansible.builtin.systemd:
    name: bluetooth.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("bluetooth.socket", multiline=True)
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_bluetooth_disabled

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

class disable_bluetooth {
  service {'bluetooth':
    enable => false,
    ensure => 'stopped',
  }
}

Rule   Deactivate Wireless Network Interfaces   [ref]

Deactivating wireless network interfaces should prevent normal usage of the wireless capability.

Verify that there are no wireless interfaces configured on the system with the following command:
$ ls -L -d /sys/class/net/*/wireless | xargs dirname | xargs basename -a
Rationale:
The use of wireless networking can introduce many different attack vectors into the organization's network. Common attack vectors such as malicious association and ad hoc networks will allow an attacker to spoof a wireless access point (AP), allowing validated systems to connect to the malicious AP and enabling the attacker to monitor and record network traffic. These malicious APs can also serve to create a man-in-the-middle attack or be used to create a denial of service to valid network resources.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_wireless_disable_interfaces
References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
cui3.1.16
disaCCI-001443, CCI-001444, CCI-002421, CCI-002418
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
ism1315, 1319
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
nistAC-18(a), AC-18(3), CM-7(a), CM-7(b), CM-6(a), MP-7
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-1.3.3
os-srgSRG-OS-000299-GPOS-00117, SRG-OS-000300-GPOS-00118, SRG-OS-000424-GPOS-00188, SRG-OS-000481-GPOS-000481
cis3.1.2
pcidss41.3.3, 1.3


if [ -n "$(find /sys/class/net/*/ -type d -name wireless)" ]; then
    interfaces=$(find /sys/class/net/*/wireless -type d -name wireless | xargs -0 dirname | xargs basename)

    for i in $interfaces; do
        ip link set dev "$i" down
        drivers=$(basename "$(readlink -f /sys/class/net/"$i"/device/driver)")
        echo "install $drivers /bin/false" >> /etc/modprobe.d/disable_wireless.conf
        modprobe -r "$drivers"
     done
fi

Complexity:low
Disruption:medium
Reboot:false
Strategy:unknown
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - PCI-DSS-Req-1.3.3
  - PCI-DSSv4-1.3
  - PCI-DSSv4-1.3.3
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy
  - wireless_disable_interfaces

- name: Service facts
  ansible.builtin.service_facts: null
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - PCI-DSS-Req-1.3.3
  - PCI-DSSv4-1.3
  - PCI-DSSv4-1.3.3
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy
  - wireless_disable_interfaces

- name: Ensure NetworkManager is installed
  ansible.builtin.package:
    name: '{{ item }}'
    state: present
  with_items:
  - NetworkManager
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - PCI-DSS-Req-1.3.3
  - PCI-DSSv4-1.3
  - PCI-DSSv4-1.3.3
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy
  - wireless_disable_interfaces

- name: NetworkManager Deactivate Wireless Network Interfaces
  command: nmcli radio wifi off
  when:
  - '''NetworkManager'' in ansible_facts.packages'
  - ansible_facts.services['NetworkManager.service'].state == 'running'
  tags:
  - NIST-800-171-3.1.16
  - NIST-800-53-AC-18(3)
  - NIST-800-53-AC-18(a)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - PCI-DSS-Req-1.3.3
  - PCI-DSSv4-1.3
  - PCI-DSSv4-1.3.3
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy
  - wireless_disable_interfaces
Group   File Permissions and Masks   Group contains 7 groups and 63 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 Ubuntu 24.04 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 33 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 33 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
cis7.1.4
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:
  - 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 shadow /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
cis7.1.8

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)
  - 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
cis7.1.2
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:
  - 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 shadow /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
cis7.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 42 /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 42 on /etc/shadow-
  file:
    path: /etc/shadow-
    group: '42'
  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
cis7.1.3
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 shadow /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
cis7.1.7

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 42 /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 42 on /etc/gshadow
  file:
    path: /etc/gshadow
    group: '42'
  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
cis7.1.1
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 /etc/security/opasswd File   [ref]

To properly set the group owner of /etc/security/opasswd, run the command:
$ sudo chgrp  /etc/security/opasswd
Rationale:
The /etc/security/opasswd file stores old passwords to prevent password reuse. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_security_opasswd
References:
cis7.1.10

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

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

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

Rule   Verify Group Who Owns /etc/security/opasswd.old File   [ref]

To properly set the group owner of /etc/security/opasswd.old, run the command:
$ sudo chgrp  /etc/security/opasswd.old
Rationale:
The /etc/security/opasswd.old file stores backups of old passwords to prevent password reuse. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_security_opasswd_old
References:
cis7.1.10

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 0 /etc/security/opasswd.old

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/security/opasswd.old
  stat:
    path: /etc/security/opasswd.old
  register: file_exists
  tags:
  - configure_strategy
  - file_groupowner_etc_security_opasswd_old
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/security/opasswd.old
  file:
    path: /etc/security/opasswd.old
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_etc_security_opasswd_old
  - 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 shadow /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
cis7.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chgrp 42 /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 42 on /etc/shadow
  file:
    path: /etc/shadow
    group: '42'
  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 Group Who Owns /etc/shells File   [ref]

To properly set the group owner of /etc/shells, run the command:
$ sudo chgrp root /etc/shells
Rationale:
The /etc/shells file contains the list of full pathnames to shells on the system. Since this file is used by many system programs this file should be protected.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_shells
References:
nistAC-3, MP-2
anssiR50
cis7.1.9

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shells
  stat:
    path: /etc/shells
  register: file_exists
  tags:
  - NIST-800-53-AC-3
  - NIST-800-53-MP-2
  - configure_strategy
  - file_groupowner_etc_shells
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/shells
  file:
    path: /etc/shells
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-3
  - NIST-800-53-MP-2
  - configure_strategy
  - file_groupowner_etc_shells
  - 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
cis7.1.4
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:
  - 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
cis7.1.8

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)
  - 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
cis7.1.2
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:
  - 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
cis7.1.6
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:
  - 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
cis7.1.3
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
cis7.1.7

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
cis7.1.1
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 /etc/security/opasswd File   [ref]

To properly set the owner of /etc/security/opasswd, run the command:
$ sudo chown root /etc/security/opasswd 
Rationale:
The /etc/security/opasswd file stores old passwords to prevent password reuse. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_security_opasswd
References:
cis7.1.10

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

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

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

Rule   Verify User Who Owns /etc/security/opasswd.old File   [ref]

To properly set the owner of /etc/security/opasswd.old, run the command:
$ sudo chown root /etc/security/opasswd.old 
Rationale:
The /etc/security/opasswd.old file stores backups of old passwords to prevent password reuse. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_security_opasswd_old
References:
cis7.1.10

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
chown 0 /etc/security/opasswd.old

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/security/opasswd.old
  stat:
    path: /etc/security/opasswd.old
  register: file_exists
  tags:
  - configure_strategy
  - file_owner_etc_security_opasswd_old
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/security/opasswd.old
  file:
    path: /etc/security/opasswd.old
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_etc_security_opasswd_old
  - 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
cis7.1.5
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 Who Owns /etc/shells File   [ref]

To properly set the owner of /etc/shells, run the command:
$ sudo chown root /etc/shells 
Rationale:
The /etc/shells file contains the list of full pathnames to shells on the system. Since this file is used by many system programs this file should be protected.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_shells
References:
nistAC-3, MP-2
anssiR50
cis7.1.9

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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shells
  stat:
    path: /etc/shells
  register: file_exists
  tags:
  - NIST-800-53-AC-3
  - NIST-800-53-MP-2
  - configure_strategy
  - file_owner_etc_shells
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/shells
  file:
    path: /etc/shells
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-3
  - NIST-800-53-MP-2
  - configure_strategy
  - file_owner_etc_shells
  - 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
cis7.1.4
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:
  - 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 0640 /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
cis7.1.8

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)
  - 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
cis7.1.2
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:
  - 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 0640 /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
cis7.1.6
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:
  - 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
cis7.1.3
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 0640 /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
cis7.1.7

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
cis7.1.1
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 /etc/security/opasswd File   [ref]

To properly set the permissions of /etc/security/opasswd, run the command:
$ sudo chmod 0600 /etc/security/opasswd
Rationale:
The /etc/security/opasswd file stores old passwords to prevent password reuse. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_security_opasswd
References:
cis7.1.10

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




chmod u-xs,g-xwrs,o-xwrt /etc/security/opasswd

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

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /etc/security/opasswd
  file:
    path: /etc/security/opasswd
    mode: u-xs,g-xwrs,o-xwrt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_security_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Rule   Verify Permissions on /etc/security/opasswd.old File   [ref]

To properly set the permissions of /etc/security/opasswd.old, run the command:
$ sudo chmod 0600 /etc/security/opasswd.old
Rationale:
The /etc/security/opasswd.old file stores backups of old passwords to prevent password reuse. Protection of this file is critical for system security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_security_opasswd_old
References:
cis7.1.10

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




chmod u-xs,g-xwrs,o-xwrt /etc/security/opasswd.old

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/security/opasswd.old
  stat:
    path: /etc/security/opasswd.old
  register: file_exists
  tags:
  - configure_strategy
  - file_permissions_etc_security_opasswd_old
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /etc/security/opasswd.old
  file:
    path: /etc/security/opasswd.old
    mode: u-xs,g-xwrs,o-xwrt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_security_opasswd_old
  - 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 0640 /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
cis7.1.5
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 Permissions on /etc/shells File   [ref]

To properly set the permissions of /etc/shells, run the command:
$ sudo chmod 0644 /etc/shells
Rationale:
The /etc/shells file contains the list of full pathnames to shells on the system. Since this file is used by many system programs this file should be protected.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_shells
References:
nistAC-3, MP-2
anssiR50
cis7.1.9

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




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

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
- name: Test for existence /etc/shells
  stat:
    path: /etc/shells
  register: file_exists
  tags:
  - NIST-800-53-AC-3
  - NIST-800-53-MP-2
  - configure_strategy
  - file_permissions_etc_shells
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/shells
  file:
    path: /etc/shells
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-53-AC-3
  - NIST-800-53-MP-2
  - configure_strategy
  - file_permissions_etc_shells
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
Group   Restrict Dynamic Mounting and Unmounting of Filesystems   Group contains 7 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   Remove autofs Package   [ref]

autofs allows automatic mounting of devices, typically including CD/DVDs and USB drives. The autofs package can be removed with the following command:
 $ apt-get remove autofs
Rationale:
With automounting enabled anyone with physical access could attach a USB drive or disc and have its contents available in the filesystem even if they lacked permissions to mount it themselves.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_autofs_removed
References:
cis2.1.1

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "autofs"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure autofs is removed
  package:
    name: autofs
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_autofs_removed

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

class remove_autofs {
  package { 'autofs':
    ensure => 'purged',
  }
}

Rule   Disable the Automounter   [ref]

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

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

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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'autofs' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

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

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

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


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

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

- name: Disable the Automounter - Collect systemd Services Present in the System
  ansible.builtin.command: systemctl -q list-unit-files --type service
  register: service_exists
  changed_when: false
  failed_when: service_exists.rc not in [0, 1]
  check_mode: false
  when: ( "autofs" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Disable the Automounter - Ensure autofs.service is Masked
  ansible.builtin.systemd:
    name: autofs.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( "autofs" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  - service_exists.stdout_lines is search("autofs.service", multiline=True)
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Unit Socket Exists - autofs.socket
  ansible.builtin.command: systemctl -q list-unit-files autofs.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( "autofs" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

- name: Disable the Automounter - Disable Socket autofs
  ansible.builtin.systemd:
    name: autofs.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( "autofs" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  - socket_file_exists.stdout_lines is search("autofs.socket", multiline=True)
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-MP-7
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_autofs_disabled

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

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

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
cis1.1.1.1

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_cramfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'cramfs' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/cramfs.conf
    regexp: install\s+cramfs
    line: install cramfs /bin/false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_cramfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'cramfs' is blacklisted
  lineinfile:
    create: true
    dest: /etc/modprobe.d/cramfs.conf
    regexp: ^blacklist cramfs$
    line: blacklist cramfs
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_cramfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

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
cis1.1.1.2

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_freevxfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'freevxfs' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/freevxfs.conf
    regexp: install\s+freevxfs
    line: install freevxfs /bin/false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_freevxfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'freevxfs' is blacklisted
  lineinfile:
    create: true
    dest: /etc/modprobe.d/freevxfs.conf
    regexp: ^blacklist freevxfs$
    line: blacklist freevxfs
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_freevxfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

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
cis1.1.1.3

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_hfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'hfs' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/hfs.conf
    regexp: install\s+hfs
    line: install hfs /bin/false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_hfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'hfs' is blacklisted
  lineinfile:
    create: true
    dest: /etc/modprobe.d/hfs.conf
    regexp: ^blacklist hfs$
    line: blacklist hfs
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_hfs_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

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
cis1.1.1.4

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_hfsplus_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'hfsplus' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/hfsplus.conf
    regexp: install\s+hfsplus
    line: install hfsplus /bin/false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_hfsplus_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'hfsplus' is blacklisted
  lineinfile:
    create: true
    dest: /etc/modprobe.d/hfsplus.conf
    regexp: ^blacklist hfsplus$
    line: blacklist hfsplus
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_hfsplus_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

if LC_ALL=C grep -q -m 1 "^install jffs2" /etc/modprobe.d/jffs2.conf ; then
	
	sed -i 's#^install jffs2.*#install jffs2 /bin/false#g' /etc/modprobe.d/jffs2.conf
else
	echo -e "\n# Disable per security requirements" >> /etc/modprobe.d/jffs2.conf
	echo "install jffs2 /bin/false" >> /etc/modprobe.d/jffs2.conf
fi

if ! LC_ALL=C grep -q -m 1 "^blacklist jffs2$" /etc/modprobe.d/jffs2.conf ; then
	echo "blacklist jffs2" >> /etc/modprobe.d/jffs2.conf
fi

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_jffs2_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'jffs2' is disabled
  lineinfile:
    create: true
    dest: /etc/modprobe.d/jffs2.conf
    regexp: install\s+jffs2
    line: install jffs2 /bin/false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_jffs2_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required

- name: Ensure kernel module 'jffs2' is blacklisted
  lineinfile:
    create: true
    dest: /etc/modprobe.d/jffs2.conf
    regexp: ^blacklist jffs2$
    line: blacklist jffs2
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.6
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - kernel_module_jffs2_disabled
  - low_complexity
  - low_severity
  - medium_disruption
  - reboot_required
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
cis1.1.2.2.2

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 ] ) ); 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
cis1.1.2.2.4

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 ] ) ); 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
cis1.1.2.2.3

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 ] ) ); 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
cis1.1.2.3.2

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 "/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
cis1.1.2.3.3

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 "/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
cis1.1.2.1.2

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
cis1.1.2.1.4

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 $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//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
cis1.1.2.1.3

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 $4}' \
                    | sed -E "s/(rw|defaults|seclabel|nosuid)(,|$)//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
cis1.1.2.7.2

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 "/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
cis1.1.2.7.4

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 $4}' \
                    | sed -E "s/(rw|defaults|seclabel|noexec)(,|$)//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
cis1.1.2.7.3

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 "/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
cis1.1.2.6.2

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" > /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
cis1.1.2.6.4

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" > /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
cis1.1.2.6.3

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" > /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
cis1.1.2.4.2

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" > /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
cis1.1.2.4.3

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" > /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
cis1.1.2.5.2

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/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
cis1.1.2.5.4

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/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
cis1.1.2.5.3

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/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 Dumps for All Users   [ref]

To disable core dumps for all users, add the following line to /etc/security/limits.conf, or to a file within the /etc/security/limits.d/ directory:
*     hard   core    0
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 trying to debug problems.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_disable_users_coredumps
References:
cis-csc1, 12, 13, 15, 16, 2, 7, 8
cobit5APO13.01, BAI04.04, DSS01.03, DSS03.05, DSS05.07
disaCCI-000366
isa-62443-2013SR 6.2, SR 7.1, SR 7.2
iso27001-2013A.12.1.3, A.17.2.1
nistCM-6, SC-7(10)
nist-csfDE.CM-1, PR.DS-4
os-srgSRG-OS-000480-GPOS-00227
cis1.5.3
pcidss43.3.1.1, 3.3.1, 3.3

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'libpam-runtime' 2>/dev/null | grep -q installed; then

SECURITY_LIMITS_FILE="/etc/security/limits.conf"

if grep -qE '^\s*\*\s+hard\s+core' $SECURITY_LIMITS_FILE; then
        sed -ri 's/(hard\s+core\s+)[[:digit:]]+/\1 0/' $SECURITY_LIMITS_FILE
else
        echo "*     hard   core    0" >> $SECURITY_LIMITS_FILE
fi

if ls /etc/security/limits.d/*.conf > /dev/null; then
        sed -ri '/^\s*\*\s+hard\s+core/d' /etc/security/limits.d/*.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
  - NIST-800-53-SC-7(10)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_users_coredumps
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Disable core dumps with limits
  lineinfile:
    dest: /etc/security/limits.conf
    regexp: ^[^#].*core
    line: '*        hard       core      0'
    create: true
  when: '"libpam-runtime" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6
  - NIST-800-53-SC-7(10)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_users_coredumps
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Disable Core Dumps for SUID programs   [ref]

To set the runtime status of the fs.suid_dumpable kernel parameter, run the following command:
$ sudo sysctl -w fs.suid_dumpable=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
fs.suid_dumpable = 0
Rationale:
The core dump of a setuid program is more likely to contain sensitive data, as the program itself runs with greater privileges than the user who initiated execution of the program. Disabling the ability for any setuid program to write a core file decreases the risk of unauthorized access of such data.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_fs_suid_dumpable
References:
hipaa164.308(a)(1)(ii)(D), 164.308(a)(3), 164.308(a)(4), 164.310(b), 164.310(c), 164.312(a), 164.312(e)
nistSI-11(a), SI-11(b)
anssiR14
cis1.5.3
pcidss43.3.1.1, 3.3.1, 3.3

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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


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

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

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

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for fs.suid_dumpable
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w fs.suid_dumpable="0"
fi

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

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

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

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

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - 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_fs_suid_dumpable

- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    contains: ^[\s]*fs.suid_dumpable.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - 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_fs_suid_dumpable

- name: Comment out any occurrences of fs.suid_dumpable from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*fs.suid_dumpable
    replace: '#fs.suid_dumpable'
  loop: '{{ find_sysctl_d.files }}'
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - 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_fs_suid_dumpable

- name: Ensure sysctl fs.suid_dumpable is set to 0
  sysctl:
    name: fs.suid_dumpable
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - 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_fs_suid_dumpable
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
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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


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

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

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

SYSCONFIG_FILE="/etc/sysctl.conf"


#
# Set runtime for kernel.randomize_va_space
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w kernel.randomize_va_space="2"
fi

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

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

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

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

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

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/
    contains: ^[\s]*kernel.randomize_va_space.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: '"linux-base" 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
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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


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

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

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

SYSCONFIG_FILE="/etc/sysctl.conf"

sysctl_kernel_yama_ptrace_scope_value='1'


#
# Set runtime for kernel.yama.ptrace_scope
#
if [[ "$OSCAP_BOOTC_BUILD" != "YES" ]] ; then
    /sbin/sysctl -q -n -w kernel.yama.ptrace_scope="$sysctl_kernel_yama_ptrace_scope_value"
fi

#
# If kernel.yama.ptrace_scope present in /etc/sysctl.conf, change value to appropriate value
#	else, add "kernel.yama.ptrace_scope = value" to /etc/sysctl.conf
#

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

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

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

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

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/
    contains: ^[\s]*kernel.yama.ptrace_scope.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: '"linux-base" 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: '"linux-base" 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: XCCDF Value sysctl_kernel_yama_ptrace_scope_value # promote to variable
  set_fact:
    sysctl_kernel_yama_ptrace_scope_value: !!str 1
  tags:
    - always

- name: Ensure sysctl kernel.yama.ptrace_scope is set
  sysctl:
    name: kernel.yama.ptrace_scope
    value: '{{ sysctl_kernel_yama_ptrace_scope_value }}'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"linux-base" 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   Services   Group contains 40 groups and 105 rules
[ref]   The best protection against vulnerable software is running less software. This section describes how to review the software which Ubuntu 24.04 installs on a system and disable software which is not needed. It then enumerates the software packages installed on a default Ubuntu 24.04 system and provides guidance about which ones can be safely disabled.

Ubuntu 24.04 provides a convenient minimal install option that essentially installs the bare necessities for a functional system. When building Ubuntu 24.04 systems, it is highly recommended to select the minimal packages and then build up the system from there.
Group   Apport Service   Group contains 1 rule
[ref]   The Apport service provides debugging and crash reporting features on Ubuntu distributions.

Rule   Disable Apport Service   [ref]

The Apport modifies certain kernel configuration values at runtime which may decrease the overall security of the system and expose sensitive data. The apport service can be disabled with the following command:
$ sudo systemctl mask --now apport.service
Rationale:
The Apport service modifies the kernel fs.suid_dumpable configuration at runtime which prevents other hardening from being persistent. Disabling the service prevents this behavior.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_apport_disabled
References:
cis1.5.5

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'apport' 2>/dev/null | grep -q installed; then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_apport_disabled
  - unknown_severity

- name: Disable Apport 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: '"apport" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_apport_disabled
  - unknown_severity

- name: Disable Apport Service - Ensure apport.service is Masked
  ansible.builtin.systemd:
    name: apport.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"apport" in ansible_facts.packages'
  - service_exists.stdout_lines is search("apport.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_apport_disabled
  - unknown_severity

- name: Unit Socket Exists - apport.socket
  ansible.builtin.command: systemctl -q list-unit-files apport.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"apport" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_apport_disabled
  - unknown_severity

- name: Disable Apport Service - Disable Socket apport
  ansible.builtin.systemd:
    name: apport.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"apport" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("apport.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_apport_disabled
  - unknown_severity

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

class disable_apport {
  service {'apport':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Avahi Server   Group contains 1 group and 2 rules
[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 2 rules
[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
cis2.1.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "avahi-daemon"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure avahi-daemon is removed
  package:
    name: avahi-daemon
    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-daemon

class remove_avahi-daemon {
  package { 'avahi-daemon':
    ensure => 'purged',
  }
}

Rule   Disable Avahi Server Software   [ref]

The avahi-daemon service can be disabled with the following command:
$ sudo systemctl mask --now avahi-daemon.service
Rationale:
Because the Avahi daemon service keeps an open network port, it is subject to network attacks. Its functionality is convenient but is only appropriate if the local network can be trusted.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_avahi-daemon_disabled
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
cis2.1.2
pcidss42.2.4, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'avahi-daemon' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

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

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

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


[customizations.services]
masked = ["avahi-daemon"]

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)
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_avahi-daemon_disabled

- name: Disable Avahi Server Software - 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: ( "avahi-daemon" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  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
  - service_avahi-daemon_disabled

- name: Disable Avahi Server Software - Ensure avahi-daemon.service is Masked
  ansible.builtin.systemd:
    name: avahi-daemon.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( "avahi-daemon" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  - service_exists.stdout_lines is search("avahi-daemon.service", multiline=True)
  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
  - service_avahi-daemon_disabled

- name: Unit Socket Exists - avahi-daemon.socket
  ansible.builtin.command: systemctl -q list-unit-files avahi-daemon.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( "avahi-daemon" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  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
  - service_avahi-daemon_disabled

- name: Disable Avahi Server Software - Disable Socket avahi-daemon
  ansible.builtin.systemd:
    name: avahi-daemon.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( "avahi-daemon" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  - socket_file_exists.stdout_lines is search("avahi-daemon.socket", multiline=True)
  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
  - service_avahi-daemon_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_avahi-daemon

class disable_avahi-daemon {
  service {'avahi-daemon':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Cron and At Daemons   Group contains 1 group and 31 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 11 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.allow exists   [ref]

The file /etc/at.allow should exist and should be used instead of /etc/at.deny.
Rationale:
Using the at.allow file to control who can run at jobs enforces this who can schedule jobs. It is easier to manage an allow list than a deny list.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_at_allow_exists
References:
cis2.4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

touch /etc/at.allow
    chown 0 /etc/at.allow
    chmod 0640 /etc/at.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_at_allow_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Add empty /etc/at.allow
  file:
    path: /etc/at.allow
    state: touch
    owner: '0'
    mode: '0640'
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - file_at_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:
cis2.4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
cis2.4.2.1
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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/at.deny file   [ref]

If /etc/at.deny exists, it must be group-owned by root. To properly set the group owner of /etc/at.deny, run the command:
$ sudo chgrp root /etc/at.deny
Rationale:
If the owner of the at.deny 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_deny
References:
cis2.4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

chgrp 0 /etc/at.deny

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_groupowner_at_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/at.deny
  stat:
    path: /etc/at.deny
  register: file_exists
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_groupowner_at_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/at.deny
  file:
    path: /etc/at.deny
    group: '0'
  when:
  - '"linux-base" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_at_deny
  - 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 crontab. To properly set the group owner of /etc/cron.allow, run the command:
$ sudo chgrp crontab /etc/cron.allow
Rationale:
If the owner of the cron.allow file is not set to crontab, 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
cis2.4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

chgrp crontab /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: '"linux-base" 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 crontab on /etc/cron.allow
  file:
    path: /etc/cron.allow
    group: crontab
  when:
  - '"linux-base" 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:
cis2.4.2.1
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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/at.deny file   [ref]

If /etc/at.deny exists, it must be owned by root. To properly set the owner of /etc/at.deny, run the command:
$ sudo chown root /etc/at.deny 
Rationale:
If the owner of the at.deny 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_deny
References:
cis2.4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

chown 0 /etc/at.deny

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_owner_at_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/at.deny
  stat:
    path: /etc/at.deny
  register: file_exists
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_owner_at_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/at.deny
  file:
    path: /etc/at.deny
    owner: '0'
  when:
  - '"linux-base" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_at_deny
  - 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
cis2.4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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:
cis2.4.2.1
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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/at.deny file   [ref]

If /etc/at.deny exists, it must have permissions 0640 or more restrictive. To properly set the permissions of /etc/at.deny, run the command:
$ sudo chmod 0640 /etc/at.deny
Rationale:
If the permissions of the at.deny 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_deny
References:
cis2.4.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

chmod u-xs,g-xws,o-xwrt /etc/at.deny

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_permissions_at_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/at.deny
  stat:
    path: /etc/at.deny
  register: file_exists
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - configure_strategy
  - file_permissions_at_deny
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwrt on /etc/at.deny
  file:
    path: /etc/at.deny
    mode: u-xs,g-xws,o-xwrt
  when:
  - '"linux-base" in ansible_facts.packages'
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_at_deny
  - 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
cis2.4.1.8
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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   Install the cron service   [ref]

The Cron service should be installed.
Rationale:
The cron service allow periodic job execution, needed for almost all administrative tasks and services (software update, log rotating, etc.). Access to cron service should be restricted to administrative accounts only.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_cron_installed
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
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-62443-20094.3.3.5.1, 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
os-srgSRG-OS-000480-GPOS-00227
cis2.4.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

DEBIAN_FRONTEND=noninteractive apt-get install -y "cron"

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


[[packages]]
name = "cron"
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_cron_installed

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

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

class install_cron {
  package { 'cron':
    ensure => 'installed',
  }
}

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 cron service can be enabled with the following command:
$ sudo systemctl enable cron.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_cron_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
cis2.4.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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


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

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_cron_enabled

- name: Enable cron Service - Enable service cron
  block:

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

  - name: Enable cron Service - Enable Service cron
    ansible.builtin.systemd:
      name: cron
      enabled: true
      state: started
      masked: false
    when:
    - '"cron" in ansible_facts.packages'
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_cron_enabled

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

class enable_cron {
  service {'cron':
    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
cis2.4.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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
cis2.4.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis2.4.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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
cis2.4.1.7
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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
cis2.4.1.4
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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
cis2.4.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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
cis2.4.1.6
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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
cis2.4.1.5
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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
cis2.4.1.2
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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   Deprecated services   Group contains 1 rule
[ref]   Some deprecated software services impact the overall system security due to their behavior (leak of confidentiality in network exchange, usage as uncontrolled communication channel, risk associated with the service due to its old age, etc.

Rule   Uninstall the nis package   [ref]

The support for Yellowpages should not be installed unless it is required.
Rationale:
NIS is the historical SUN service for central account management, more and more replaced by LDAP. NIS does not support efficiently security constraints, ACL, etc. and should not be used.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_nis_removed
References:
cis2.2.1

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "nis"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure nis is removed
  package:
    name: nis
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_nis_removed

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

class remove_nis {
  package { 'nis':
    ensure => 'purged',
  }
}
Group   DHCP   Group contains 1 group and 3 rules
[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 3 rules
[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 isc-dhcp-server package can be removed with the following command:
$ apt-get remove isc-dhcp-server
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
cis2.1.3
pcidss42.2.4, 2.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "isc-dhcp-server"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure isc-dhcp-server is removed
  package:
    name: isc-dhcp-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
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_dhcp_removed

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
include remove_isc-dhcp-server

class remove_isc-dhcp-server {
  package { 'isc-dhcp-server':
    ensure => 'purged',
  }
}

Rule   Disable DHCPD6 Service   [ref]

The dhcp6 service should be disabled on any system that does not need to act as a DHCP server. The isc-dhcp-server6 service can be disabled with the following command:
$ sudo systemctl mask --now isc-dhcp-server6.service
Rationale:
Unmanaged or unintentionally activated DHCP servers may provide faulty information to clients, interfering with the operation of a legitimate site DHCP server if there is one.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_dhcpd6_disabled
References:
cis2.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'isc-dhcp-server6.service'
"$SYSTEMCTL_EXEC" disable 'isc-dhcp-server6.service'
"$SYSTEMCTL_EXEC" mask 'isc-dhcp-server6.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files isc-dhcp-server6.socket; then
    "$SYSTEMCTL_EXEC" stop 'isc-dhcp-server6.socket'
    "$SYSTEMCTL_EXEC" mask 'isc-dhcp-server6.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'isc-dhcp-server6.service' || true

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: isc-dhcp-server6.service
        enabled: false
        mask: true
      - name: isc-dhcp-server6.socket
        enabled: false
        mask: true


[customizations.services]
masked = ["isc-dhcp-server6"]

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
  - service_dhcpd6_disabled

- name: Disable DHCPD6 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dhcpd6_disabled

- name: Disable DHCPD6 Service - Ensure isc-dhcp-server6.service is Masked
  ansible.builtin.systemd:
    name: isc-dhcp-server6.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("isc-dhcp-server6.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dhcpd6_disabled

- name: Unit Socket Exists - isc-dhcp-server6.socket
  ansible.builtin.command: systemctl -q list-unit-files isc-dhcp-server6.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dhcpd6_disabled

- name: Disable DHCPD6 Service - Disable Socket isc-dhcp-server6
  ansible.builtin.systemd:
    name: isc-dhcp-server6.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("isc-dhcp-server6.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dhcpd6_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_isc-dhcp-server6

class disable_isc-dhcp-server6 {
  service {'isc-dhcp-server6':
    enable => false,
    ensure => 'stopped',
  }
}

Rule   Disable DHCP Service   [ref]

The dhcpd service should be disabled on any system that does not need to act as a DHCP server. The isc-dhcp-server service can be disabled with the following command:
$ sudo systemctl mask --now isc-dhcp-server.service
Rationale:
Unmanaged or unintentionally activated DHCP servers may provide faulty information to clients, interfering with the operation of a legitimate site DHCP server if there is one.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_dhcpd_disabled
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
cis2.1.3

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


[customizations.services]
masked = ["isc-dhcp-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
  - medium_severity
  - no_reboot_needed
  - service_dhcpd_disabled

- name: Disable DHCP 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: '"linux-base" 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
  - medium_severity
  - no_reboot_needed
  - service_dhcpd_disabled

- name: Disable DHCP Service - Ensure isc-dhcp-server.service is Masked
  ansible.builtin.systemd:
    name: isc-dhcp-server.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("isc-dhcp-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
  - medium_severity
  - no_reboot_needed
  - service_dhcpd_disabled

- name: Unit Socket Exists - isc-dhcp-server.socket
  ansible.builtin.command: systemctl -q list-unit-files isc-dhcp-server.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" 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
  - medium_severity
  - no_reboot_needed
  - service_dhcpd_disabled

- name: Disable DHCP Service - Disable Socket isc-dhcp-server
  ansible.builtin.systemd:
    name: isc-dhcp-server.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("isc-dhcp-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
  - medium_severity
  - no_reboot_needed
  - service_dhcpd_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_isc-dhcp-server

class disable_isc-dhcp-server {
  service {'isc-dhcp-server':
    enable => false,
    ensure => 'stopped',
  }
}
Group   DNS Server   Group contains 1 group and 4 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 2 rules
[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 Ubuntu 24.04 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:
$ apt-get 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
cis2.1.4

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

# CAUTION: This remediation script will remove bind9
#	   from the system, and may remove any packages
#	   that depend on bind9. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "bind9"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure bind9 is removed
  package:
    name: bind9
    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_bind9

class remove_bind9 {
  package { 'bind9':
    ensure => 'purged',
  }
}

Rule   Disable named Service   [ref]

The named service can be disabled with the following command:
$ sudo systemctl mask --now named.service
Rationale:
All network services involve some risk of compromise due to implementation flaws and should be disabled if possible.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_named_disabled
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
cis2.1.4

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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
  - medium_severity
  - no_reboot_needed
  - service_named_disabled

- name: Disable named 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: '"linux-base" 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
  - medium_severity
  - no_reboot_needed
  - service_named_disabled

- name: Disable named Service - Ensure named.service is Masked
  ansible.builtin.systemd:
    name: named.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("named.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
  - medium_severity
  - no_reboot_needed
  - service_named_disabled

- name: Unit Socket Exists - named.socket
  ansible.builtin.command: systemctl -q list-unit-files named.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" 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
  - medium_severity
  - no_reboot_needed
  - service_named_disabled

- name: Disable named Service - Disable Socket named
  ansible.builtin.systemd:
    name: named.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("named.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
  - medium_severity
  - no_reboot_needed
  - service_named_disabled

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

class disable_named {
  service {'named':
    enable => false,
    ensure => 'stopped',
  }
}

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:
$ apt-get 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:
cis2.1.5

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "dnsmasq"

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',
  }
}

Rule   Disable dnsmasq Service   [ref]

The dnsmasq service can be disabled with the following command:
$ sudo systemctl mask --now dnsmasq.service
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: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_dnsmasq_disabled
References:
cis2.1.5

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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
  - service_dnsmasq_disabled

- name: Disable dnsmasq 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dnsmasq_disabled

- name: Disable dnsmasq Service - Ensure dnsmasq.service is Masked
  ansible.builtin.systemd:
    name: dnsmasq.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("dnsmasq.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dnsmasq_disabled

- name: Unit Socket Exists - dnsmasq.socket
  ansible.builtin.command: systemctl -q list-unit-files dnsmasq.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dnsmasq_disabled

- name: Disable dnsmasq Service - Disable Socket dnsmasq
  ansible.builtin.systemd:
    name: dnsmasq.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("dnsmasq.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_dnsmasq_disabled

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

class disable_dnsmasq {
  service {'dnsmasq':
    enable => false,
    ensure => 'stopped',
  }
}
Group   FTP Server   Group contains 1 group and 4 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 2 rules
[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:
 $ apt-get 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
cis2.1.6

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "vsftpd"

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   Disable vsftpd Service   [ref]

The vsftpd service can be disabled with the following command:
$ sudo systemctl mask --now vsftpd.service
Rationale:
Running FTP server software provides a network-based avenue of attack, and should be disabled if not needed. Furthermore, the FTP protocol is unencrypted and creates a risk of compromising sensitive information.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_vsftpd_disabled
References:
cis-csc11, 14, 3, 9
cobit5BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06
disaCCI-001436
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
cis2.1.6

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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
  - medium_severity
  - no_reboot_needed
  - service_vsftpd_disabled

- name: Disable vsftpd 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: '"linux-base" 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
  - medium_severity
  - no_reboot_needed
  - service_vsftpd_disabled

- name: Disable vsftpd Service - Ensure vsftpd.service is Masked
  ansible.builtin.systemd:
    name: vsftpd.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("vsftpd.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
  - medium_severity
  - no_reboot_needed
  - service_vsftpd_disabled

- name: Unit Socket Exists - vsftpd.socket
  ansible.builtin.command: systemctl -q list-unit-files vsftpd.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" 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
  - medium_severity
  - no_reboot_needed
  - service_vsftpd_disabled

- name: Disable vsftpd Service - Disable Socket vsftpd
  ansible.builtin.systemd:
    name: vsftpd.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("vsftpd.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
  - medium_severity
  - no_reboot_needed
  - service_vsftpd_disabled

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

class disable_vsftpd {
  service {'vsftpd':
    enable => false,
    ensure => 'stopped',
  }
}

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:
$ apt-get 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:
cis2.2.6
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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "ftp"

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',
  }
}

Rule   Remove tnftp Package   [ref]

tnftp an enhanced FTP client, is the user interface to the Internet standard File Transfer Protocol. The program allows a user to transfer files to and from a remote network site. The ftp package can be removed with the following command:
$ apt-get remove ftp
Rationale:
Unless there is a need to run the system using Internet standard File Transfer Protocol (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_tnftp_removed
References:
cis2.2.6

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "tnftp"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure tnftp is removed
  package:
    name: tnftp
    state: absent
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_tnftp_removed

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

class remove_tnftp {
  package { 'tnftp':
    ensure => 'purged',
  }
}
Group   Web Server   Group contains 2 groups and 4 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 2 rules
[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 apache2 Package   [ref]

The apache2 package can be removed with the following command:
$ apt-get remove apache2
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
cis2.1.18

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

# CAUTION: This remediation script will remove apache2
#	   from the system, and may remove any packages
#	   that depend on apache2. Execute this
#	   remediation AFTER testing on a non-production
#	   system!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "apache2"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure apache2 is removed
  package:
    name: apache2
    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_apache2

class remove_apache2 {
  package { 'apache2':
    ensure => 'purged',
  }
}

Rule   Disable apache2 Service   [ref]

The apache2 service can be disabled with the following command:
$ sudo systemctl mask --now apache2.service
Rationale:
Running web server software provides a network-based avenue of attack, and should be disabled if not needed.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_httpd_disabled
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
cis2.1.18

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'apache2.service'
"$SYSTEMCTL_EXEC" disable 'apache2.service'
"$SYSTEMCTL_EXEC" mask 'apache2.service'
# Disable socket activation if we have a unit file for it
if "$SYSTEMCTL_EXEC" -q list-unit-files apache2.socket; then
    "$SYSTEMCTL_EXEC" stop 'apache2.socket'
    "$SYSTEMCTL_EXEC" mask 'apache2.socket'
fi
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'apache2.service' || true

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

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    systemd:
      units:
      - name: apache2.service
        enabled: false
        mask: true
      - name: apache2.socket
        enabled: false
        mask: true


[customizations.services]
masked = ["apache2"]

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_httpd_disabled
  - unknown_severity

- name: Disable apache2 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: '"linux-base" 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_httpd_disabled
  - unknown_severity

- name: Disable apache2 Service - Ensure apache2.service is Masked
  ansible.builtin.systemd:
    name: apache2.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("apache2.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_httpd_disabled
  - unknown_severity

- name: Unit Socket Exists - apache2.socket
  ansible.builtin.command: systemctl -q list-unit-files apache2.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" 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_httpd_disabled
  - unknown_severity

- name: Disable apache2 Service - Disable Socket apache2
  ansible.builtin.systemd:
    name: apache2.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("apache2.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_httpd_disabled
  - unknown_severity

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_apache2

class disable_apache2 {
  service {'apache2':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Disable NGINX if Possible   Group contains 2 rules
[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:
$ apt-get 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
cis2.1.18

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "nginx"

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',
  }
}

Rule   Disable nginx Service   [ref]

The nginx service can be disabled with the following command:
$ sudo systemctl mask --now nginx.service
Rationale:
Running web server software provides a network-based avenue of attack, and should be disabled if not needed.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_nginx_disabled
References:
cis2.1.18

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nginx_disabled
  - unknown_severity

- name: Disable nginx 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nginx_disabled
  - unknown_severity

- name: Disable nginx Service - Ensure nginx.service is Masked
  ansible.builtin.systemd:
    name: nginx.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("nginx.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nginx_disabled
  - unknown_severity

- name: Unit Socket Exists - nginx.socket
  ansible.builtin.command: systemctl -q list-unit-files nginx.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nginx_disabled
  - unknown_severity

- name: Disable nginx Service - Disable Socket nginx
  ansible.builtin.systemd:
    name: nginx.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("nginx.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_nginx_disabled
  - unknown_severity

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

class disable_nginx {
  service {'nginx':
    enable => false,
    ensure => 'stopped',
  }
}
Group   IMAP and POP3 Server   Group contains 1 group 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 Dovecot   Group contains 2 rules
[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-core package can be removed with the following command:
$ apt-get remove dovecot-core
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:
cis2.1.8

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "dovecot-core"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure dovecot-core is removed
  package:
    name: dovecot-core
    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-core

class remove_dovecot-core {
  package { 'dovecot-core':
    ensure => 'purged',
  }
}

Rule   Disable Dovecot Service   [ref]

The dovecot service can be disabled with the following command:
$ sudo systemctl mask --now dovecot.service
Rationale:
Running an IMAP or POP3 server provides a network-based avenue of attack, and should be disabled if not needed.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_dovecot_disabled
References:
cis2.1.8

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_dovecot_disabled
  - unknown_severity

- name: Disable Dovecot 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_dovecot_disabled
  - unknown_severity

- name: Disable Dovecot Service - Ensure dovecot.service is Masked
  ansible.builtin.systemd:
    name: dovecot.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("dovecot.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_dovecot_disabled
  - unknown_severity

- name: Unit Socket Exists - dovecot.socket
  ansible.builtin.command: systemctl -q list-unit-files dovecot.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_dovecot_disabled
  - unknown_severity

- name: Disable Dovecot Service - Disable Socket dovecot
  ansible.builtin.systemd:
    name: dovecot.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("dovecot.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_dovecot_disabled
  - unknown_severity

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

class disable_dovecot {
  service {'dovecot':
    enable => false,
    ensure => 'stopped',
  }
}
Group   LDAP   Group contains 2 groups and 3 rules
[ref]   LDAP is a popular directory service, that is, a standardized way of looking up information from a central database. Ubuntu 24.04 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. Ubuntu 24.04 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 Ubuntu 24.04 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 lapd-utils package can be removed with the following command:
$ apt-get remove lapd-utils
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:
cis2.2.5

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "openldap-clients"

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   Configure OpenLDAP Server   Group contains 2 rules
[ref]   This section details some security-relevant settings for an OpenLDAP server.

Rule   Uninstall openldap-servers Package   [ref]

The slapd package is not installed by default on a Ubuntu 24.04 system. It is needed only by the OpenLDAP server, not by the clients which use LDAP for authentication. If the system is not intended for use as an LDAP Server it should be removed.
Rationale:
Unnecessary packages should not be installed to decrease the attack surface of the system. While this software is clearly essential on an LDAP server, it is not necessary on typical desktop or workstation systems.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_openldap-servers_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
cis2.1.7

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "slapd"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure slapd is removed
  package:
    name: slapd
    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_openldap-servers_removed

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

class remove_slapd {
  package { 'slapd':
    ensure => 'purged',
  }
}

Rule   Disable LDAP Server (slapd)   [ref]

The Lightweight Directory Access Protocol (LDAP) is a service that provides a method for looking up information from a central database.
Rationale:
If the system will not need to act as an LDAP server, it is recommended that the software be disabled to reduce the potential attack surface.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_slapd_disabled
References:
cis2.1.7

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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
  - service_slapd_disabled

- name: Disable LDAP Server (slapd) - 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_slapd_disabled

- name: Disable LDAP Server (slapd) - Ensure slapd.service is Masked
  ansible.builtin.systemd:
    name: slapd.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("slapd.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_slapd_disabled

- name: Unit Socket Exists - slapd.socket
  ansible.builtin.command: systemctl -q list-unit-files slapd.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_slapd_disabled

- name: Disable LDAP Server (slapd) - Disable Socket slapd
  ansible.builtin.systemd:
    name: slapd.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("slapd.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_slapd_disabled

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

class disable_slapd {
  service {'slapd':
    enable => false,
    ensure => 'stopped',
  }
}
Group   NFS and RPC   Group contains 2 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 2 rules
[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 2 rules
[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   Uninstall rpcbind Package   [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 package can be removed with the following command:
$ apt-get remove rpcbind
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_package_rpcbind_removed
References:
cis2.1.12

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "rpcbind"

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_rpcbind_removed

- name: Ensure rpcbind is removed
  package:
    name: rpcbind
    state: absent
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - package_rpcbind_removed

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

class remove_rpcbind {
  package { 'rpcbind':
    ensure => 'purged',
  }
}

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:
cis2.1.12
pcidss42.2.4, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


[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: '"linux-base" 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:
  - '"linux-base" 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: '"linux-base" 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:
  - '"linux-base" 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   Network Time Protocol   Group contains 5 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://help.ubuntu.com/lts/serverguide/NTP.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   The Chronyd service is enabled   [ref]

chrony is a daemon which implements the Network Time Protocol (NTP) 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 enable Chronyd service, you can run: # systemctl enable chronyd.service 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_service_chronyd_enabled
References:
disaCCI-004923
ism0988, 1405
os-srgSRG-OS-000355-GPOS-00143
cis2.3.3.3

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { dpkg-query --show --showformat='${db:Status-Status}\n' 'chrony' 2>/dev/null | grep -q installed; }; then

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_chronyd_enabled

- name: The Chronyd service is enabled - Enable service chronyd
  block:

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

  - name: The Chronyd service is enabled - Enable Service chronyd
    ansible.builtin.systemd:
      name: chronyd
      enabled: true
      state: started
      masked: false
    when:
    - '"chrony" in ansible_facts.packages'
  when:
  - '"linux-base" in ansible_facts.packages'
  - '"chrony" in ansible_facts.packages'
  tags:
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_chronyd_enabled

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

class enable_chronyd {
  service {'chronyd':
    enable => true,
    ensure => 'running',
  }
}

Rule   Enable systemd_timesyncd Service   [ref]

The systemd_timesyncd service can be enabled with the following command:
$ sudo systemctl enable systemd_timesyncd.service
Rationale:
Enabling the systemd_timesyncd service ensures that this host uses the ntp protocol to fetch time data from a ntp server. Synchronizing time is essential for authentication services such as Kerberos, but it is also important for maintaining accurate logs and auditing possible security breaches.

Additional information on Ubuntu network time protocol is available at https://help.ubuntu.com/lts/serverguide/NTP.html.en.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_service_timesyncd_enabled
References:
cis-csc1, 14, 15, 16, 3, 5, 6
cobit5APO11.04, BAI03.05, DSS05.04, DSS05.07, MEA02.01
disaCCI-000160
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), AU-8(1)(a)
nist-csfPR.PT-1
pcidssReq-10.4
cis2.3.2.2
pcidss410.6.1, 10.6

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { ( ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'chrony' 2>/dev/null | grep -q installed ) && ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ntp' 2>/dev/null | grep -q installed ) ); }; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'systemd-timesyncd.service'
"$SYSTEMCTL_EXEC" start 'systemd-timesyncd.service'
"$SYSTEMCTL_EXEC" enable 'systemd-timesyncd.service'

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
- 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
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.1
  - enable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_timesyncd_enabled

- name: Enable systemd_timesyncd Service - Enable service systemd-timesyncd
  block:

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

  - name: Enable systemd_timesyncd Service - Enable Service systemd-timesyncd
    ansible.builtin.systemd:
      name: systemd-timesyncd
      enabled: true
      state: started
      masked: false
    when:
    - '"systemd" in ansible_facts.packages'
  when:
  - '"linux-base" in ansible_facts.packages'
  - ( not ( "chrony" in ansible_facts.packages ) and not ( "ntp" in ansible_facts.packages
    ) )
  tags:
  - NIST-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.1
  - enable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_timesyncd_enabled

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

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

Rule   Chrony Configure Pool and Server   [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/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_configure_pool_and_server
References:
disaCCI-000160, CCI-001891
ism0988, 1405
nistCM-6(a), AU-8(1)(a)
pcidssReq-10.4.3
anssiR71
cis2.3.3.1

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { dpkg-query --show --showformat='${db:Status-Status}\n' 'chrony' 2>/dev/null | grep -q installed; }; then

var_multiple_time_servers='0.ubuntu.pool.ntp.org,1.ubuntu.pool.ntp.org,2.ubuntu.pool.ntp.org,3.ubuntu.pool.ntp.org'

var_multiple_time_pools='0.ubuntu.pool.ntp.org,1.ubuntu.pool.ntp.org,2.ubuntu.pool.ntp.org,3.ubuntu.pool.ntp.org'


config_file="/etc/chrony/chrony.conf"

# Check and configigure servers in /etc/chrony/chrony.conf
IFS="," read -a SERVERS <<< $var_multiple_time_servers
for srv in "${SERVERS[@]}"
do
   NTP_SRV=$(grep -w $srv $config_file)
   if [[ ! "$NTP_SRV" == "server "* ]]
   then
     time_server="server $srv"
     echo $time_server >> "$config_file"
   fi
done

# Check and configure pools in /etc/chrony/chrony.conf
IFS="," read -a POOLS <<< $var_multiple_time_pools
for srv in "${POOLS[@]}"
do
   NTP_POOL=$(grep -w $srv $config_file)
   if [[ ! "$NTP_POOL" == "pool "* ]]
   then
     time_server="pool $srv"
     echo $time_server >> "$config_file"
   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-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4.3
  - chronyd_configure_pool_and_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.ubuntu.pool.ntp.org,1.ubuntu.pool.ntp.org,2.ubuntu.pool.ntp.org,3.ubuntu.pool.ntp.org
  tags:
    - always
- name: XCCDF Value var_multiple_time_pools # promote to variable
  set_fact:
    var_multiple_time_pools: !!str 0.ubuntu.pool.ntp.org,1.ubuntu.pool.ntp.org,2.ubuntu.pool.ntp.org,3.ubuntu.pool.ntp.org
  tags:
    - always

- name: Chrony Configure Pool and Server - Add missing / update wrong records for
    remote time servers
  ansible.builtin.lineinfile:
    path: /etc/chrony/chrony.conf
    regexp: ^\s*\bserver\b\s*\b{{ item }}\b$
    state: present
    line: server {{ item }}
    create: true
  with_items:
  - '{{ var_multiple_time_servers.split(",") }}'
  when:
  - '"linux-base" 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
  - chronyd_configure_pool_and_server
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Chrony Configure Pool and Server - Add missing / update wrong records for
    remote time pools
  ansible.builtin.lineinfile:
    path: /etc/chrony/chrony.conf
    regexp: ^\s*\bpool\b\s*\b{{ item }}\b$
    state: present
    line: pool {{ item }}
    create: true
  with_items:
  - '{{ var_multiple_time_pools.split(",") }}'
  when:
  - '"linux-base" 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
  - chronyd_configure_pool_and_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, user variable in /etc/chrony/chrony.conf is set to _chrony or is absent:
user _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:
cis2.3.3.2
pcidss410.6.3, 10.6

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { dpkg-query --show --showformat='${db:Status-Status}\n' 'chrony' 2>/dev/null | grep -q installed; }; then

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

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

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

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

Rule   Configure Systemd Timesyncd Servers   [ref]

systemd-timesyncd is a daemon that has been added for synchronizing the system clock across the network. The systemd-timesyncd daemon implements: - Implements an SNTP client - Runs with minimal privileges - Saves the current clock to disk every time a new NTP sync has been acquired - Is hooked up with networkd to only operate when network connectivity is available Add or edit server or pool lines to /etc/systemd/timesyncd.conf as appropriate:
server <remote-server>
Multiple servers may be configured.
Rationale:
Configuring systemd-timesyncd ensures time synchronization is working properly.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_timesyncd_configured
References:
disaCCI-001891
pcidssReq-10.4.3
cis2.3.2.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed && { dpkg-query --show --showformat='${db:Status-Status}\n' 'systemd' 2>/dev/null | grep -q installed; }; then

var_multiple_time_servers='0.ubuntu.pool.ntp.org,1.ubuntu.pool.ntp.org,2.ubuntu.pool.ntp.org,3.ubuntu.pool.ntp.org'

IFS=',' read -r -a time_servers_array <<< "$var_multiple_time_servers"
preferred_ntp_servers_array=("${time_servers_array[@]:0:2}")
preferred_ntp_servers=$( echo "${preferred_ntp_servers_array[@]}"|sed -e 's/\s\+/,/g' )
fallback_ntp_servers_array=("${time_servers_array[@]:2}")
fallback_ntp_servers=$( echo "${fallback_ntp_servers_array[@]}"|sed -e 's/\s\+/,/g' )

IFS=" " mapfile -t current_cfg_arr < <(ls -1 /etc/systemd/timesyncd.d/* 2>/dev/null)
config_file="/etc/systemd/timesyncd.d/oscap-remedy.conf"
current_cfg_arr+=( "/etc/systemd/timesyncd.conf" )
# Comment existing NTP FallbackNTP settings
for current_cfg in "${current_cfg_arr[@]}"
do
    sed -i 's/^NTP/#&/g' "$current_cfg"
    sed -i 's/^FallbackNTP/#&/g' "$current_cfg"
done
# Create /etc/systemd/timesyncd.d if it doesn't exist
if [ ! -d "/etc/systemd/timesyncd.d" ]
then 
    mkdir /etc/systemd/timesyncd.d
fi
# Set primary fallback NTP servers in drop-in configuration
echo "NTP=$preferred_ntp_servers" >> "$config_file"
echo "FallbackNTP=$fallback_ntp_servers" >> "$config_file"

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-DSS-Req-10.4.3
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_timesyncd_configured
- name: XCCDF Value var_multiple_time_servers # promote to variable
  set_fact:
    var_multiple_time_servers: !!str 0.ubuntu.pool.ntp.org,1.ubuntu.pool.ntp.org,2.ubuntu.pool.ntp.org,3.ubuntu.pool.ntp.org
  tags:
    - always

- name: Configure Systemd Timesyncd Servers - Set Primary NTP Servers
  ansible.builtin.set_fact:
    preferred_ntp_servers: '{{ var_multiple_time_servers.split(",") | slice(2)| first
      | join(",") }}'
  when:
  - '"linux-base" in ansible_facts.packages'
  - '"systemd" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-10.4.3
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_timesyncd_configured

- name: Configure Systemd Timesyncd Servers - Set Fallback NTP Servers
  ansible.builtin.set_fact:
    fallback_ntp_servers: '{{ var_multiple_time_servers.split(",") | slice(2)| list
      | last | join(",") }}'
  when:
  - '"linux-base" in ansible_facts.packages'
  - '"systemd" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-10.4.3
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_timesyncd_configured

- name: Configure Systemd Timesyncd Servers - Add missing / update wrong records for
    NTP servers
  ansible.builtin.lineinfile:
    path: /etc/systemd/timesyncd.d/oscap-remedy.conf
    regexp: ^\s*NTP\s*=
    state: present
    line: NTP={{ preferred_ntp_servers }}
    create: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - '"systemd" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-10.4.3
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_timesyncd_configured

- name: Configure Systemd Timesyncd Servers - Add missing / update wrong records for
    fallback servers
  ansible.builtin.lineinfile:
    path: /etc/systemd/timesyncd.d/oscap-remedy.conf
    regexp: ^\s*FallbackNTP\s*=
    state: present
    line: FallbackNTP={{ fallback_ntp_servers }}
    create: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - '"systemd" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-10.4.3
  - configure_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_timesyncd_configured
Group   Obsolete Services   Group contains 6 groups and 12 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 Ubuntu 24.04 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   Xinetd   Group contains 2 rules
[ref]   The xinetd service acts as a dedicated listener for some network services (mostly, obsolete ones) and can be used to provide access controls and perform some logging. It has been largely obsoleted by other features, and it is not installed by default. The older Inetd service is not even available as part of Ubuntu 24.04.

Rule   Uninstall xinetd Package   [ref]

The xinetd package can be removed with the following command:
$ apt-get remove xinetd
Rationale:
Removing the xinetd package decreases the risk of the xinetd service's accidental (or intentional) activation.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_package_xinetd_removed
References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000305
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
anssiR62
cis2.1.19
pcidss42.2.4, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "xinetd"

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:
  - 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
  - low_severity
  - no_reboot_needed
  - package_xinetd_removed

- name: Ensure xinetd is removed
  package:
    name: xinetd
    state: absent
  when: '"linux-base" in ansible_facts.packages'
  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
  - low_severity
  - no_reboot_needed
  - package_xinetd_removed

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

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

Rule   Disable xinetd Service   [ref]

The xinetd service can be disabled with the following command:
$ sudo systemctl mask --now xinetd.service
Rationale:
The xinetd service provides a dedicated listener service for some programs, which is no longer necessary for commonly-used network services. Disabling it ensures that these uncommon services are not running, and also prevents attacks against xinetd itself.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_xinetd_disabled
References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
cui3.4.7
disaCCI-000305
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
cis2.1.19

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

- name: Disable xinetd Service - 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: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

- name: Disable xinetd Service - Ensure xinetd.service is Masked
  ansible.builtin.systemd:
    name: xinetd.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("xinetd.service", multiline=True)
  tags:
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

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

- name: Disable xinetd Service - Disable Socket xinetd
  ansible.builtin.systemd:
    name: xinetd.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("xinetd.socket", multiline=True)
  tags:
  - NIST-800-171-3.4.7
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_xinetd_disabled

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

class disable_xinetd {
  service {'xinetd':
    enable => false,
    ensure => 'stopped',
  }
}
Group   NIS   Group contains 2 rules
[ref]   The Network Information Service (NIS), also known as 'Yellow Pages' (YP), and its successor NIS+ have been made obsolete by Kerberos, LDAP, and other modern centralized authentication services. NIS should not be used because it suffers from security problems inherent in its design, such as inadequate protection of important authentication information.

Rule   Uninstall ypserv Package   [ref]

The ypserv package can be removed with the following command:
$ apt-get remove ypserv
Rationale:
The NIS service provides an unencrypted authentication service which does not provide for the confidentiality and integrity of user passwords or the remote session. Removing the ypserv package decreases the risk of the accidental (or intentional) activation of NIS or NIS+ services.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_package_ypserv_removed
References:
cis-csc11, 12, 14, 15, 3, 8, 9
cobit5APO13.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.04, DSS05.02, DSS05.03, DSS05.05, DSS06.06
disaCCI-000381
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
isa-62443-20094.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3
isa-62443-2013SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6
iso27001-2013A.11.2.6, A.12.1.2, A.12.5.1, A.12.6.2, A.13.1.1, A.13.2.1, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.6.2.1, A.6.2.2, A.9.1.2
nistCM-7(a), CM-7(b), CM-6(a), IA-5(1)(c)
nist-csfPR.AC-3, PR.IP-1, PR.PT-3, PR.PT-4
pcidssReq-2.2.2
os-srgSRG-OS-000095-GPOS-00049
anssiR62
cis2.1.10
pcidss42.2.4, 2.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "ypserv"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure ypserv is removed
  package:
    name: ypserv
    state: absent
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-IA-5(1)(c)
  - PCI-DSS-Req-2.2.2
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_ypserv_removed

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

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

Rule   Disable ypserv Service   [ref]

The ypserv service, which allows the system to act as a client in a NIS or NIS+ domain, should be disabled. The ypserv service can be disabled with the following command:
$ sudo systemctl mask --now ypserv.service
Rationale:
Disabling the ypserv service ensures the system is not acting as a client in a NIS or NIS+ domain. This service should be disabled unless in use.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_ypserv_disabled
References:
cis2.1.10

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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
  - service_ypserv_disabled

- name: Disable ypserv 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypserv_disabled

- name: Disable ypserv Service - Ensure ypserv.service is Masked
  ansible.builtin.systemd:
    name: ypserv.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("ypserv.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypserv_disabled

- name: Unit Socket Exists - ypserv.socket
  ansible.builtin.command: systemctl -q list-unit-files ypserv.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypserv_disabled

- name: Disable ypserv Service - Disable Socket ypserv
  ansible.builtin.systemd:
    name: ypserv.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("ypserv.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_ypserv_disabled

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

class disable_ypserv {
  service {'ypserv':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Rlogin, Rsh, and Rexec   Group contains 2 rules
[ref]   The Berkeley r-commands are legacy services which allow cleartext remote access and have an insecure trust model.

Rule   Uninstall rsh Package   [ref]

The rsh-client package contains the client commands for the rsh services
Rationale:
These legacy clients contain numerous security exposures and have been replaced with the more secure SSH package. Even if the server is removed, it is best to ensure the clients are also removed to prevent users from inadvertently attempting to use these commands and therefore exposing their credentials. Note that removing the rsh-client package removes the clients for rsh,rcp, and rlogin.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_package_rsh_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
cis2.2.2
pcidss42.2.4, 2.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "rsh"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure rsh is removed
  package:
    name: rsh
    state: absent
  tags:
  - NIST-800-171-3.1.13
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - package_rsh_removed
  - unknown_severity

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

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

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
cis7.2.10

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}\n' 'rsh-server' 2>/dev/null | grep -q installed; then

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

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Chat/Messaging Services   Group contains 1 rule
[ref]   The talk software makes it possible for users to send and receive messages across systems through a terminal session.

Rule   Uninstall talk Package   [ref]

The talk package contains the client program for the Internet talk protocol, which allows the user to chat with other users on different systems. Talk is a communication program which copies lines from one terminal to the terminal of another user. The talk package can be removed with the following command:
$ apt-get remove talk
Rationale:
The talk software presents a security risk as it uses unencrypted protocols for communications. Removing the talk package decreases the risk of the accidental (or intentional) activation of talk client program.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_talk_removed
References:
hipaa164.308(a)(4)(i), 164.308(b)(1), 164.308(b)(3), 164.310(b), 164.312(e)(1), 164.312(e)(2)(ii)
anssiR62
cis2.2.3
pcidss42.2.4, 2.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "talk"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure talk is removed
  package:
    name: talk
    state: absent
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_talk_removed

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

class remove_talk {
  package { 'talk':
    ensure => 'purged',
  }
}
Group   Telnet   Group contains 1 rule
[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   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 Ubuntu 24.04.
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
cis2.2.4
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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "telnet"

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 2 rules
[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 tftpd-hpa Package   [ref]

The tftpd-hpa package can be removed with the following command:
 $ apt-get remove tftpd-hpa
Rationale:
Removing the tftpd-hpa 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
cis2.1.16
pcidss42.2.4, 2.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "tftpd-hpa"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure tftpd-hpa is removed
  package:
    name: tftpd-hpa
    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_tftpd-hpa

class remove_tftpd-hpa {
  package { 'tftpd-hpa':
    ensure => 'purged',
  }
}

Rule   Disable tftpd-hpa Service   [ref]

The tftpd-hpa service should be disabled. The tftpd-hpa service can be disabled with the following command:
$ sudo systemctl mask --now tftpd-hpa.service
Rationale:
Disabling the tftpd-hpa service ensures the system is not acting as a TFTP server, which does not provide encryption or authentication.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_service_tftp_disabled
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
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
cis2.1.16

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


[customizations.services]
masked = ["tftpd-hpa"]

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
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_tftp_disabled

- name: Disable tftpd-hpa 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: '"linux-base" 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
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_tftp_disabled

- name: Disable tftpd-hpa Service - Ensure tftpd-hpa.service is Masked
  ansible.builtin.systemd:
    name: tftpd-hpa.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("tftpd-hpa.service", multiline=True)
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_tftp_disabled

- name: Unit Socket Exists - tftpd-hpa.socket
  ansible.builtin.command: systemctl -q list-unit-files tftpd-hpa.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" 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
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_tftp_disabled

- name: Disable tftpd-hpa Service - Disable Socket tftpd-hpa
  ansible.builtin.systemd:
    name: tftpd-hpa.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("tftpd-hpa.socket", multiline=True)
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_tftp_disabled

Complexity:low
Disruption:low
Reboot:false
Strategy:enable
include disable_tftpd-hpa

class disable_tftpd-hpa {
  service {'tftpd-hpa':
    enable => false,
    ensure => 'stopped',
  }
}

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:
$ apt-get 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:
cis2.1.13

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "rsync"

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',
  }
}

Rule   Ensure rsyncd service is disabled   [ref]

The rsyncd service can be disabled with the following command:
$ sudo systemctl mask --now rsyncd.service
Rationale:
The rsyncd service presents a security risk as it uses unencrypted protocols for communication.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_rsyncd_disabled
References:
cis2.1.13
pcidss42.2.4, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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
  - medium_severity
  - no_reboot_needed
  - service_rsyncd_disabled

- name: Ensure rsyncd service is disabled - 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: '"linux-base" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyncd_disabled

- name: Ensure rsyncd service is disabled - Ensure rsync.service is Masked
  ansible.builtin.systemd:
    name: rsync.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("rsync.service", multiline=True)
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyncd_disabled

- name: Unit Socket Exists - rsync.socket
  ansible.builtin.command: systemctl -q list-unit-files rsync.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyncd_disabled

- name: Ensure rsyncd service is disabled - Disable Socket rsync
  ansible.builtin.systemd:
    name: rsync.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("rsync.socket", multiline=True)
  tags:
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.4
  - disable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyncd_disabled

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

class disable_rsync {
  service {'rsync':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Print Support   Group contains 2 rules
[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:
$ apt-get 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
cis2.1.11

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "cups"

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',
  }
}

Rule   Disable the CUPS Service   [ref]

The cups service can be disabled with the following command:
$ sudo systemctl mask --now cups.service
Rationale:
Turn off unneeded services to reduce attack surface.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_cups_disabled
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
cis2.1.11

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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_cups_disabled
  - unknown_severity

- name: Disable the CUPS 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: '"linux-base" 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_cups_disabled
  - unknown_severity

- name: Disable the CUPS Service - Ensure cups.service is Masked
  ansible.builtin.systemd:
    name: cups.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("cups.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_cups_disabled
  - unknown_severity

- name: Unit Socket Exists - cups.socket
  ansible.builtin.command: systemctl -q list-unit-files cups.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" 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_cups_disabled
  - unknown_severity

- name: Disable the CUPS Service - Disable Socket cups
  ansible.builtin.systemd:
    name: cups.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("cups.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_cups_disabled
  - unknown_severity

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

class disable_cups {
  service {'cups':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Proxy Server   Group contains 1 group and 2 rules
[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 2 rules
[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:
 $ apt-get 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:
cis2.1.17

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "squid"

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',
  }
}

Rule   Disable Squid   [ref]

The squid service can be disabled with the following command:
$ sudo systemctl mask --now squid.service
Rationale:
Running proxy server software provides a network-based avenue of attack, and should be removed if not needed.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_service_squid_disabled
References:
cis2.1.17

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'squid' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

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

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

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


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

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_squid_disabled
  - unknown_severity

- name: Disable Squid - 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: ( "squid" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_squid_disabled
  - unknown_severity

- name: Disable Squid - Ensure squid.service is Masked
  ansible.builtin.systemd:
    name: squid.service
    state: stopped
    enabled: false
    masked: true
  when:
  - ( "squid" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  - service_exists.stdout_lines is search("squid.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_squid_disabled
  - unknown_severity

- name: Unit Socket Exists - squid.socket
  ansible.builtin.command: systemctl -q list-unit-files squid.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: ( "squid" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_squid_disabled
  - unknown_severity

- name: Disable Squid - Disable Socket squid
  ansible.builtin.systemd:
    name: squid.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - ( "squid" in ansible_facts.packages and "linux-base" in ansible_facts.packages
    )
  - socket_file_exists.stdout_lines is search("squid.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_squid_disabled
  - unknown_severity

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

class disable_squid {
  service {'squid':
    enable => false,
    ensure => 'stopped',
  }
}
Group   Samba(SMB) Microsoft Windows File Sharing Server   Group contains 1 group and 2 rules
[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 2 rules
[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:
 $ apt-get 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:
cis2.1.14

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!

DEBIAN_FRONTEND=noninteractive apt-get remove -y "samba"

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',
  }
}

Rule   Disable Samba   [ref]

The smb service can be disabled with the following command:
$ sudo systemctl mask --now smb.service
Rationale:
Running a Samba server provides a network-based avenue of attack, and should be disabled if not needed.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_service_smb_disabled
References:
disaCCI-001436
cis2.1.14

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

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

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


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

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_smb_disabled

- name: Disable Samba - 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: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_smb_disabled

- name: Disable Samba - Ensure smbd.service is Masked
  ansible.builtin.systemd:
    name: smbd.service
    state: stopped
    enabled: false
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - service_exists.stdout_lines is search("smbd.service", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_smb_disabled

- name: Unit Socket Exists - smbd.socket
  ansible.builtin.command: systemctl -q list-unit-files smbd.socket
  register: socket_file_exists
  changed_when: false
  failed_when: socket_file_exists.rc not in [0, 1]
  check_mode: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_smb_disabled

- name: Disable Samba - Disable Socket smbd
  ansible.builtin.systemd:
    name: smbd.socket
    enabled: false
    state: stopped
    masked: true
  when:
  - '"linux-base" in ansible_facts.packages'
  - socket_file_exists.stdout_lines is search("smbd.socket", multiline=True)
  tags:
  - disable_strategy
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - service_smb_disabled

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

class disable_smbd {
  service {'smbd':
    enable => false,
    ensure => 'stopped',
  }
}
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 snmp package provides the snmpd service. The snmp package can be removed with the following command:
$ apt-get remove 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:
cis2.1.15
pcidss42.2.4, 2.2

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

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

DEBIAN_FRONTEND=noninteractive apt-get remove -y "snmpd"

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
- name: Ensure snmpd is removed
  package:
    name: snmpd
    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_snmpd

class remove_snmpd {
  package { 'snmpd':
    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
cis2.1.15

Complexity:low
Disruption:low
Reboot:false
Strategy:disable
# Remediation is applicable only in certain platforms
if ( dpkg-query --show --showformat='${db:Status-Status}\n' 'snmp' 2>/dev/null | grep -q installed && dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed ); then

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

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

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


[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: ( "snmp" in ansible_facts.packages and "linux-base" 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:
  - ( "snmp" in ansible_facts.packages and "linux-base" 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: ( "snmp" in ansible_facts.packages and "linux-base" 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:
  - ( "snmp" in ansible_facts.packages and "linux-base" 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 23 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 18 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
cis5.1.7
pcidss48.2.8, 8.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

var_sshd_set_keepalive='3'


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 3
  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: '"linux-base" 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 300
        


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
cis5.1.7
pcidss48.2.8, 8.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

sshd_idle_timeout_value='300'


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 300
  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: '"linux-base" 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
cis5.1.10
pcidss48.3.1, 8.3

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis5.1.19
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis5.1.11
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis5.1.21
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis5.1.22
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis5.1.5

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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
cis5.1.4
pcidss42.2.6, 2.2

Rule   Set LogLevel to INFO   [ref]

The INFO parameter specifices that record login and logout activity will be logged.
The default SSH configuration sets the log level to INFO. The appropriate configuration is used if no value is set for LogLevel.
To explicitly specify the log level in SSH, add or correct the following line in /etc/ssh/sshd_config.d/00-complianceascode-hardening.conf:
LogLevel INFO
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 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: 
low
Rule ID:xccdf_org.ssgproject.content_rule_sshd_set_loglevel_info
References:
nistAC-17(a), CM-6(a)
cis5.1.14

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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*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/01-complianceascode-reinforce-os-defaults.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*LogLevel\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' "LogLevel INFO" > "/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:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_loglevel_info

- name: Set LogLevel to INFO
  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/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*{{ "LogLevel"| regex_escape }}\s+
      line: LogLevel INFO
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-AC-17(a)
  - NIST-800-53-CM-6(a)
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_set_loglevel_info

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
cis5.1.16
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
cis5.1.17
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
cis5.1.18
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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   Use Only Strong Ciphers   [ref]

Limit the ciphers to strong algorithms. Counter (CTR) mode is also preferred over cipher-block chaining (CBC) mode. The following line in /etc/ssh/sshd_config demonstrates use of those ciphers:
Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
The man page sshd_config(5) contains a list of supported ciphers.
Rationale:
Based on research conducted at various institutions, it was determined that the symmetric portion of the SSH Transport Protocol (as described in RFC 4253) has security weaknesses that allowed recovery of up to 32 bits of plaintext from a block of ciphertext that was encrypted with the Cipher Block Chaining (CBD) method. From that research, new Counter mode algorithms (as described in RFC4344) were designed that are not vulnerable to these types of attacks and these algorithms are now recommended for standard use.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_use_strong_ciphers
References:
cis5.1.6

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

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

cp "/etc/ssh/sshd_config" "/etc/ssh/sshd_config.bak"
# Insert at the beginning of the file
printf '%s\n' "Ciphers aes128-ctr,aes192-ctr,aes256-ctr,chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com" > "/etc/ssh/sshd_config"
cat "/etc/ssh/sshd_config.bak" >> "/etc/ssh/sshd_config"
# Clean up after ourselves.
rm "/etc/ssh/sshd_config.bak"

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

Rule   Use Only Strong Key Exchange algorithms   [ref]

Limit the Key Exchange to strong algorithms. The following line in /etc/ssh/sshd_config demonstrates use of those:
KexAlgorithms sntrup761x25519-sha512@openssh.com,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256
        
Rationale:
Key exchange is any method in cryptography by which cryptographic keys are exchanged between two parties, allowing use of a cryptographic algorithm. If the sender and receiver wish to exchange encrypted messages, each must be equipped to encrypt messages to be sent and decrypt messages received
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_use_strong_kex
References:
pcidssReq-2.3
cis5.1.12
pcidss42.2.7, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

sshd_strong_kex='sntrup761x25519-sha512@openssh.com,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256'


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

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

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

Complexity:low
Disruption:low
Reboot:false
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - PCI-DSS-Req-2.3
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.7
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_use_strong_kex
- name: XCCDF Value sshd_strong_kex # promote to variable
  set_fact:
    sshd_strong_kex: !!str sntrup761x25519-sha512@openssh.com,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256
  tags:
    - always

- name: Use Only Strong Key Exchange algorithms
  block:

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

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

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)(?i)^\s*KexAlgorithms\s+
      line: KexAlgorithms {{ sshd_strong_kex }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - PCI-DSS-Req-2.3
  - PCI-DSSv4-2.2
  - PCI-DSSv4-2.2.7
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_use_strong_kex

Rule   Use Only Strong MACs   [ref]

Limit the MACs to strong hash algorithms. The following line in /etc/ssh/sshd_config demonstrates use of those MACs:
MACs umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
        
Rationale:
MD5 and 96-bit MAC algorithms are considered weak and have been shown to increase exploitability in SSH downgrade attacks. Weak algorithms continue to have a great deal of attention as a weak spot that can be exploited with expanded computing power. An attacker that breaks the algorithm could take advantage of a MiTM position to decrypt the SSH tunnel and capture credentials and information
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sshd_use_strong_macs
References:
cis5.1.15

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; then

sshd_strong_macs='umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1'


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

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

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^MACs\\>" "/etc/ssh/sshd_config"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^MACs\\>.*/$escaped_formatted_output/gi" "/etc/ssh/sshd_config"
else
    if [[ -s "/etc/ssh/sshd_config" ]] && [[ -n "$(tail -c 1 -- "/etc/ssh/sshd_config" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "/etc/ssh/sshd_config"
    fi
    printf '%s\n' "$formatted_output" >> "/etc/ssh/sshd_config"
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:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_use_strong_macs
- name: XCCDF Value sshd_strong_macs # promote to variable
  set_fact:
    sshd_strong_macs: !!str umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
  tags:
    - always

- name: Use Only Strong MACs
  block:

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

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

  - name: Insert correct line to /etc/ssh/sshd_config
    lineinfile:
      path: /etc/ssh/sshd_config
      create: true
      regexp: (?i)(?i)^\s*MACs\s+
      line: MACs {{ sshd_strong_macs }}
      state: present
      insertbefore: BOF
      validate: /usr/sbin/sshd -t -f %s
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sshd_use_strong_macs

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
cis5.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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 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
cis5.1.1

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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 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
cis5.1.1
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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:
  - '"linux-base" 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.
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
cis5.1.2
pcidss42.2.6, 2.2

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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"
    
    
    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: '"linux-base" 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: '"linux-base" 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
cis5.1.3
pcidss42.2.6, 2.2

Complexity:low
Disruption:low
Reboot:false
Strategy:configure
# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'linux-base' 2>/dev/null | grep -q ^installed; 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: '"linux-base" 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: '"linux-base" 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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