Configure auditd flush priority

An XCCDF Rule

Description

The auditd service can be configured to synchronously write audit event data to disk. Add or correct the following line in /etc/audit/auditd.conf to ensure that audit event data is fully synchronized with the log files on the disk:

flush =

Rationale

Audit data should be synchronously written to disk to ensure log integrity. These parameters assure that all audit event data is fully synchronized with the log files on the disk.

ID: xccdf_org.ssgproject.content_rule_auditd_data_retention_flush
Severity: Medium
References: 1 12 13 14 15 16 2 3 5 6 7 8 9

APO10.01 APO10.03 APO10.04 APO10.05 APO11.04 BAI03.05 DSS01.03 DSS03.05 DSS05.02 DSS05.04 DSS05.05 DSS05.07 MEA01.01 MEA01.02 MEA01.03 MEA01.04 MEA01.05 MEA02.01

3.3.1

CCI-001576

164.308(a)(1)(ii)(D) 164.308(a)(3)(ii)(A) 164.308(a)(5)(ii)(C) 164.312(a)(2)(i) 164.312(b) 164.312(d) 164.312(e)

4.3.2.6.7 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

SR 2.10 SR 2.11 SR 2.12 SR 2.8 SR 2.9 SR 6.1 SR 6.2

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

CIP-004-6 R2.2.3 CIP-004-6 R3.3 CIP-007-3 R5.2 CIP-007-3 R5.3.1 CIP-007-3 R5.3.2 CIP-007-3 R5.3.3 CIP-007-3 R6.5

AU-11 CM-6(a)

DE.CM-1 DE.CM-3 DE.CM-7 ID.SC-4 PR.PT-1

SRG-OS-000480-GPOS-00227
Updated: about 1 year ago

- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.3.1
  - NIST-800-53-AU-11  - NIST-800-53-CM-6(a)
  - auditd_data_retention_flush
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_auditd_flush # promote to variable
  set_fact:
    var_auditd_flush: !!str <xccdf-1.2:sub xmlns:xccdf-1.2="http://checklists.nist.gov/xccdf/1.2" idref="xccdf_org.ssgproject.content_value_var_auditd_flush" use="legacy"/>
  tags:
    - always

- name: Configure auditd Flush Priority
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: ^\s*flush\s*=\s*.*$
    line: flush = {{ var_auditd_flush }}
    state: present
    create: true
  when:
  - '"audit" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.3.1
  - NIST-800-53-AU-11
  - NIST-800-53-CM-6(a)
  - auditd_data_retention_flush
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

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

var_auditd_flush='<xccdf-1.2:sub xmlns:xccdf-1.2="http://checklists.nist.gov/xccdf/1.2" idref="xccdf_org.ssgproject.content_value_var_auditd_flush" use="legacy"/>'

AUDITCONFIG=/etc/audit/auditd.conf

# if flush is present, flush param edited to var_auditd_flush
# else flush param is defined by var_auditd_flush
#
# the freq param is only used for values 'incremental' and 'incremental_async' and will be
# commented out if flush != incremental or flush != incremental_async
#
# if flush == incremental or flush == incremental_async && freq param is not defined, it 
# will be defined as the package-default value of 20

grep -q ^flush $AUDITCONFIG && \
  sed -i 's/^flush.*/flush = '"$var_auditd_flush"'/g' $AUDITCONFIG
if ! [ $? -eq 0 ]; then
  echo "flush = $var_auditd_flush" >> $AUDITCONFIG
fi

if ! [ "$var_auditd_flush" == "incremental" ] && ! [ "$var_auditd_flush" == "incremental_async" ]; then
  sed -i 's/^freq/##freq/g' $AUDITCONFIG
elif [ "$var_auditd_flush" == "incremental" ] || [ "$var_auditd_flush" == "incremental_async" ]; then
  grep -q freq $AUDITCONFIG && \
    sed -i 's/^#\+freq/freq/g' $AUDITCONFIG
  if ! [ $? -eq 0 ]; then
    echo "freq = 20" >> $AUDITCONFIG
  fi
fi

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

Configure auditd flush priority

Description

Rationale

Remediation - Ansible

Remediation - Shell Script