A file integrity tool must be used at least weekly to check for unauthorized file changes, particularly the addition of unauthorized system libraries or binaries, or for unauthorized modification to authorized system libraries or binaries.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-11945	GEN000220	SV-38178r1_rule	DCSL-1	Medium

Description
Changes in system libraries, binaries and other critical system files can indicate compromise or significant system events such as patching needing to be checked by automated processes and the results reviewed by the SA. NOTE: For MAC I systems, increase the frequency to daily.

STIG	Date
Red Hat Enterprise Linux 5 Security Technical Implementation Guide	2013-07-03

Details

Check Text ( C-37562r2_chk )
Determine if there is an automated job, scheduled to run weekly or more frequently, to run the file integrity tool to check for unauthorized additions to system libraries. The check can be done using Advanced Intrusion Detection Environment (AIDE) which is part of the Red Hat Enterprise Linux (RHEL) distribution. Other file integrity software may be used but must be checked manually. Procedure: Check the root crontab (crontab -l) and the global crontabs in /etc/crontab, /etc/cron.d/* for the presence of an "aide" job to run at least weekly, which should have asterisks (*) in columns 3, 4, and 5. Check the weekly cron directory (/etc/cron.weekly) for any script running "aide --check" or "aide -C" or simply "aide". If there is not, this is a finding. NOTE: For MAC I systems, increase the frequency to daily.

Check Text ( C-37562r2_chk )

Determine if there is an automated job, scheduled to run weekly or more frequently, to run the file integrity tool to check for unauthorized additions to system libraries. The check can be done using Advanced Intrusion Detection Environment (AIDE) which is part of the Red Hat Enterprise Linux (RHEL) distribution. Other file integrity software may be used but must be checked manually.

Procedure:
Check the root crontab (crontab -l) and the global crontabs in /etc/crontab, /etc/cron.d/* for the presence of an "aide" job to run at least weekly, which should have asterisks (*) in columns 3, 4, and 5.

Check the weekly cron directory (/etc/cron.weekly) for any script running "aide --check" or "aide -C" or simply "aide". If there is not, this is a finding.

NOTE: For MAC I systems, increase the frequency to daily.

Fix Text (F-32806r2_fix)
Establish an automated job, scheduled to run weekly or more frequently, to run "aide --check" which is the file integrity tool to check for unauthorized system libraries or binaries. NOTE: For MAC I systems, increase the frequency to daily.