Verify Permissions on /etc/audit/rules.d/*.rules

Description

To properly set the permissions of /etc/audit/rules.d/*.rules, run the command:

$ sudo chmod 0640 /etc/audit/rules.d/*.rules

Rationale

Without the capability to restrict the roles and individuals that can select which events are audited, unauthorized personnel may be able to prevent the auditing of critical events. Misconfigured audits may degrade the system’s performance by overwhelming the audit log. Misconfigured audits may also make it more difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one.

Remediation

Shell script

The following script can be run on the host to remediate the issue.

#!/bin/bash

find -H /etc/audit/rules.d/ -maxdepth 1 -perm /u+xs,g+xws,o+xwrt  -type f -regextype posix-extended -regex '^.*rules$' -exec chmod u-xs,g-xws,o-xwrt {} \;

Ansible playbook

The following playbook can be run with Ansible to remediate the issue.

- name: Find /etc/audit/rules.d/ file(s)
  command: find -H /etc/audit/rules.d/ -maxdepth 1 -perm /u+xs,g+xws,o+xwrt  -type
    f -regextype posix-extended -regex "^.*rules$"
  register: files_found
  changed_when: false
  failed_when: false
  check_mode: false
  tags:
  - DISA-STIG-UBTU-20-010133
  - NIST-800-53-AU-12(b)
  - configure_strategy
  - file_permissions_etc_audit_rulesd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Set permissions for /etc/audit/rules.d/ file(s)
  file:
    path: '{{ item }}'
    mode: u-xs,g-xws,o-xwrt
    state: file
  with_items:
  - '{{ files_found.stdout_lines }}'
  tags:
  - DISA-STIG-UBTU-20-010133
  - NIST-800-53-AU-12(b)
  - configure_strategy
  - file_permissions_etc_audit_rulesd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed