The audit system must be configured to audit all attempts to alter system time through adjtimex.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-208882	OL6-00-000165	SV-208882r505921_rule		Low

Description
Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.

STIG	Date
Oracle Linux 6 Security Technical Implementation Guide	2020-09-10

Details

Check Text ( C-9135r357626_chk )
To determine if the system is configured to audit calls to the "adjtimex" system call, run the following command: $ sudo grep -w "adjtimex" /etc/audit/audit.rules -a always,exit -F arch=b32 -S adjtimex -k audit_time_rules -a always,exit -F arch=b64 -S adjtimex -k audit_time_rules If the system is 64-bit and does not return a rule for both "b32" and "b64" architectures, this is a finding. If the system is not configured to audit the "adjtimex" system call, this is a finding.

Check Text ( C-9135r357626_chk )

To determine if the system is configured to audit calls to the "adjtimex" system call, run the following command:

$ sudo grep -w "adjtimex" /etc/audit/audit.rules

-a always,exit -F arch=b32 -S adjtimex -k audit_time_rules
-a always,exit -F arch=b64 -S adjtimex -k audit_time_rules

If the system is 64-bit and does not return a rule for both "b32" and "b64" architectures, this is a finding.
If the system is not configured to audit the "adjtimex" system call, this is a finding.

Fix Text (F-9135r357627_fix)
On a 32-bit system, add the following to "/etc/audit/audit.rules": # audit_time_rules -a always,exit -F arch=b32 -S adjtimex -k audit_time_rules If the system is 64-bit, then also add the following: # audit_time_rules -a always,exit -F arch=b64 -S adjtimex -k audit_time_rules