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SOCLE-RUN-AUD-025// Audit (auditd daemon)mediumpersistent config

Configure auditd mail_acct Action on Low Disk Space

Ensures action_mail_acct = root in /etc/audit/auditd.conf so auditd emails an administrator when audit disk space runs low.

Checked against the content of a persistent configuration file, the source of truth that survives reboots.

A pass proves? running now✓ on disk✓ survives rebootthe qualified verdict →
Debian 12CIS 1.1.0Debian 13CIS 1.0.0FedoraRHEL 10 / Rocky 10 / AlmaLinux 10RHEL 8 / Rocky 8 / AlmaLinux 8CIS 4.0.0RHEL 9 / Rocky 9 / AlmaLinux 9CIS 2.0.0Ubuntu 22.04CIS 3.0.0Ubuntu 24.04CIS 1.0.0Ubuntu 26.04
One check, maps to 3 standards

A mapping is a cross-reference to where each standard places this requirement, anchored and cross-validated, not a claim of equivalence. A passing check is evidence toward these references, how to read it.

Why this rule matters

Email sent to the root account is typically aliased to the administrators of the system, who can take appropriate action.

What Pavois checks

Pavois greps /etc/audit/auditd.conf for action_mail_acct = root and expects ok. auditd.conf is the daemon's single configuration file (no drop-in fragmentation), so reading it reflects exactly what auditd will use after its next reload, the effective notification target.

describe command('grep -qiE \'^[[:space:]]*action_mail_acct[[:space:]]*=[[:space:]]*(root)\b\' /etc/audit/auditd.conf 2>/dev/null && echo ok || echo ko') do
  its('stdout.strip') { should eq 'ok' }
end

How to verify it is applied

Run grep -i action_mail_acct /etc/audit/auditd.conf. Expected: action_mail_acct = root. After reloading auditd, the setting is live.

Inspect & investigate

  • /var/log/audit/audit.log and the auditd journal (journalctl -u auditd) record disk-space events and the daemon's reactions.
  • A local mail transport must be present for the alert to reach root (check the mail spool / mailq).

Remediation

No automated remediation is wired for this rule. Apply manually, set action_mail_acct = root in /etc/audit/auditd.conf, then reload with augenrules --load or systemctl reload auditd. Ensure a working MTA so root's mail is delivered to admins.

Pavois applies this with its own harden engine, the plan below, not a shell script:

file/etc/audit/auditd.conf
keyaction_mail_acct
resourceconf_line
serviceauditd
valueroot
pavois harden plan local

where the target is local, a user@host SSH alias, or a container , Docs

Impact & precautions

Without a notification account, admins learn of audit-storage exhaustion only after records are already being lost. Setting it is harmless; the real prerequisite is a functioning mail path (alias root → a monitored mailbox), otherwise the alert is generated but never read.

Standards mapping

StandardReferenceTypeVersionConfidence
CIS6.2.2.4, 6.3.2.4directper OS, see the benchmark tablehigh
NIST3.3.1, AU-5(2), AU-5(a), CM-6(a), IA-5(1)supporting800-53 Rev 5 · 800-171 Rev 2 (pinned)medium
DISA STIGUBTU-22-653025, UBTU-24-900980directper OS STIG releasehigh

Each reference is a cross-reference anchored in the upstream benchmark and cross-validated against the SCAP Security Guide and ansible-lockdown, not a claim of equivalence. Direct = a prescriptive, line-level requirement; supporting = an abstract control family (NIST) the check provides evidence toward. How to read a mapping.

Sources & references