Verify User Who Owns /etc/security/opasswd File

Description

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.

Remediation

Shell script

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

#!/bin/bash

newown=""
if id "0" >/dev/null 2>&1; then
  newown="0"
fi

if [[ -z "$newown" ]]; then
  >&2 echo "0 is not a defined user on the system"
else
if ! stat -c "%u %U" "/etc/security/opasswd" | grep -E -w -q "0"; then
    chown --no-dereference "$newown" /etc/security/opasswd
fi

fi

Ansible playbook

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

- name: Set the file_owner_etc_security_opasswd_newown variable if represented by
    uid
  ansible.builtin.set_fact:
    file_owner_etc_security_opasswd_newown: '0'
  tags:
  - configure_strategy
  - file_owner_etc_security_opasswd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /etc/security/opasswd
  ansible.builtin.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 on /etc/security/opasswd
  ansible.builtin.file:
    path: /etc/security/opasswd
    follow: false
    owner: '{{ file_owner_etc_security_opasswd_newown }}'
  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