The audit system must be configured to audit all discretionary access control permission modifications using chown.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-51167	OL6-00-000185	SV-65377r1_rule		Low

Description
The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

STIG	Date
Oracle Linux 6 Security Technical Implementation Guide	2015-03-23

Details

Check Text ( C-53571r1_chk )
To determine if the system is configured to audit calls to the "chown" system call, run the following command: # auditctl -l | grep syscall | grep chown If the system is configured to audit this activity, it will return several lines. If no lines are returned, this is a finding.

Fix Text (F-55975r1_fix)

At a minimum, the audit system should collect file permission changes for all users and root. Add the following to "/etc/audit/audit.rules": -a always,exit -F arch=b32 -S chown -F auid>=500 -F auid!=4294967295 \ -k perm_mod -a always,exit -F arch=b32 -S chown -F auid=0 -k perm_mod If the system is 64-bit, then also add the following: -a always,exit -F arch=b64 -S chown -F auid>=500 -F auid!=4294967295 \ -k perm_mod -a always,exit -F arch=b64 -S chown -F auid=0 -k perm_mod