Configure Systemd Timer Execution of AIDE

An XCCDF Rule

Description

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.

ID: xccdf_org.ssgproject.content_rule_aide_periodic_checking_systemd_timer
Severity: Medium
References: 1 11 12 13 14 15 16 2 3 5 7 8 9

5.10.1.3

APO01.06 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

CCI-001744 CCI-002699 CCI-002702

4.3.4.3.2 4.3.4.3.3 4.3.4.4.4

SR 3.1 SR 3.3 SR 3.4 SR 3.8 SR 4.1 SR 6.2 SR 7.6

A.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

CM-6(a) SI-7 SI-7(1)

DE.CM-1 DE.CM-7 PR.DS-1 PR.DS-6 PR.DS-8 PR.IP-1 PR.IP-3

Req-11.5

SRG-OS-000363-GPOS-00150 SRG-OS-000446-GPOS-00200 SRG-OS-000447-GPOS-00201

R76

11.5.2
Updated: about 1 month ago

Remediation Templates

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

# create unit file for periodic aide database check
cat > /etc/systemd/system/aidecheck.service <<EOF[Unit]
Description=Aide Check
[Service]
Type=simple
ExecStart=/usr/sbin/aide --check
[Install]
WantedBy=multi-user.target
EOF

# create unit file for the aide check timer
cat > /etc/systemd/system/aidecheck.timer <<EOF
[Unit]
Description=Aide check every day at 5AM
[Timer]
OnCalendar=*-*-* 05:00:00
Unit=aidecheck.service
[Install]
WantedBy=multi-user.target
EOF

#  setup service unit files attributes
chown root:root /etc/systemd/system/aidecheck.*
chmod 0644 /etc/systemd/system/aidecheck.*

# enable the aide related services
systemctl daemon-reload
systemctl enable aidecheck.service
systemctl --now enable aidecheck.timer

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

- 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 - Define AIDE Periodic Check Service
  ansible.builtin.blockinfile:
    create: true
    dest: /etc/systemd/system/aidecheck.service
    owner: root
    group: root
    mode: '0644'
    block: |
      [Unit]
      Description=Aide Check
      [Service]
      Type=simple
      ExecStart=/usr/sbin/aide --check
      [Install]
      WantedBy=multi-user.target
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"aide" 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 - Define AIDE Periodic Check Service
    Timer
  ansible.builtin.blockinfile:
    create: true
    dest: /etc/systemd/system/aidecheck.timer
    owner: root
    group: root
    mode: '0644'
    block: |
      [Unit]
      Description=Aide check every day at 5AM
      [Timer]
      OnCalendar=*-*-* 05:00:00
      Unit=aidecheck.service
      [Install]
      WantedBy=multi-user.target
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"aide" 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 is Enabled
  ansible.builtin.systemd:
    name: aidecheck.service
    enabled: true
    daemon_reload: true
    masked: false
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"aide" 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: aidecheck.timer
    state: started
    enabled: true
    daemon_reload: true
    masked: false
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - '"aide" 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

Configure Systemd Timer Execution of AIDE

Description

Rationale

Remediation Templates

A Shell Script

An Ansible Snippet