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

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-38561	RHEL-06-000194	SV-50362r3_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
Red Hat Enterprise Linux 6 Security Technical Implementation Guide	2017-04-28

Details

Check Text ( None )
None

Fix Text (F-43509r2_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 lsetxattr -F auid>=500 -F auid!=4294967295 \ -k perm_mod -a always,exit -F arch=b32 -S lsetxattr -F auid=0 -k perm_mod If the system is 64-bit, then also add the following: -a always,exit -F arch=b64 -S lsetxattr -F auid>=500 -F auid!=4294967295 \ -k perm_mod -a always,exit -F arch=b64 -S lsetxattr -F auid=0 -k perm_mod

Fix Text (F-43509r2_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 lsetxattr -F auid>=500 -F auid!=4294967295 \
-k perm_mod
-a always,exit -F arch=b32 -S lsetxattr -F auid=0 -k perm_mod

If the system is 64-bit, then also add the following:

-a always,exit -F arch=b64 -S lsetxattr -F auid>=500 -F auid!=4294967295 \
-k perm_mod
-a always,exit -F arch=b64 -S lsetxattr -F auid=0 -k perm_mod