The Ubuntu operating system must be configured so that audit configuration files are not write-accessible by unauthorized users.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-219234	UBTU-18-010311	SV-219234r610963_rule		Medium

Description
Without the capability to restrict which roles and individuals 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.

Description

Without the capability to restrict which roles and individuals 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.

STIG	Date
Canonical Ubuntu 18.04 LTS Security Technical Implementation Guide	2021-06-16

Details

Check Text ( C-20959r305030_chk )
Verify that "/etc/audit/audit.rules", "/etc/audit/rules.d/" and "/etc/audit/auditd.conf" files have a mode of 0640 or less permissive by using the following command: # sudo ls -al /etc/audit/ /etc/audit/rules.d/ /etc/audit/: drwxr-x--- 3 root root 4096 Nov 25 11:02 . drwxr-xr-x 130 root root 12288 Dec 19 13:42 .. -rw-r----- 1 root root 804 Nov 25 11:01 auditd.conf -rw-r----- 1 root root 9128 Dec 27 09:56 audit.rules -rw-r----- 1 root root 9373 Dec 27 09:56 audit.rules.prev -rw-r----- 1 root root 127 Feb 7 2018 audit-stop.rules drwxr-x--- 2 root root 4096 Dec 27 09:56 rules.d /etc/audit/rules.d/: drwxr-x--- 2 root root 4096 Dec 27 09:56 . drwxr-x--- 3 root root 4096 Nov 25 11:02 .. -rw-r----- 1 root root 10357 Dec 27 09:56 stig.rules If "/etc/audit/audit.rule","/etc/audit/rules.d/" or "/etc/audit/auditd.conf" file have a mode more permissive than "0640", this is a finding.

Check Text ( C-20959r305030_chk )

Verify that "/etc/audit/audit.rules", "/etc/audit/rules.d/*" and "/etc/audit/auditd.conf" files have a mode of 0640 or less permissive by using the following command:

# sudo ls -al /etc/audit/ /etc/audit/rules.d/

/etc/audit/:

drwxr-x--- 3 root root 4096 Nov 25 11:02 .

drwxr-xr-x 130 root root 12288 Dec 19 13:42 ..

-rw-r----- 1 root root 804 Nov 25 11:01 auditd.conf

-rw-r----- 1 root root 9128 Dec 27 09:56 audit.rules

-rw-r----- 1 root root 9373 Dec 27 09:56 audit.rules.prev

-rw-r----- 1 root root 127 Feb 7 2018 audit-stop.rules

drwxr-x--- 2 root root 4096 Dec 27 09:56 rules.d

/etc/audit/rules.d/:

drwxr-x--- 2 root root 4096 Dec 27 09:56 .

drwxr-x--- 3 root root 4096 Nov 25 11:02 ..

-rw-r----- 1 root root 10357 Dec 27 09:56 stig.rules

If "/etc/audit/audit.rule","/etc/audit/rules.d/*" or "/etc/audit/auditd.conf" file have a mode more permissive than "0640", this is a finding.

Fix Text (F-20958r305031_fix)
Configure "/etc/audit/audit.rules", "/etc/audit/rules.d/" and "/etc/audit/auditd.conf" files to have a mode of 0640 by using the following command: # chmod -R 0640 /etc/audit/audit.{rules,conf} /etc/audit/rules.d/* Note: The "root" account must be used to edit any files in the /etc/audit and /etc/audit/rules.d/ directories.