.Xauthority or X*.hosts (or equivalent) file(s) must be used to restrict access to the X server.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-12016	GEN005220	SV-12517r2_rule	ECCD-1 ECCD-2	Medium

Description
If access to the X server is not restricted, a user's X session may be compromised.

STIG	Date
UNIX SRG	2013-03-26

Details

Check Text ( C-7979r2_chk )
Determine if the X server is running. Procedure: # ps -ef \|grep X Determine if xauth is being used. Procedure: # xauth xauth> list If the above command sequence does not show any host other than the localhost, then xauth is not being used. Search the system for an X.hosts files, where is a display number that may be used to limit X window connections. If no files are found, X.hosts files are not being used. If the X.hosts files contain any unauthorized hosts, this is a finding. If both xauth and X*.hosts files are not being used, this is a finding.

Check Text ( C-7979r2_chk )

Determine if the X server is running.
Procedure:
# ps -ef |grep X

Determine if xauth is being used.
Procedure:
# xauth
xauth> list

If the above command sequence does not show any host other than the localhost, then xauth is not being used.

Search the system for an X*.hosts files, where * is a display number that may be used to limit X window connections. If no files are found, X*.hosts files are not being used. If the X*.hosts files contain any unauthorized hosts, this is a finding.

If both xauth and X*.hosts files are not being used, this is a finding.

Fix Text (F-11275r2_fix)
Create an X.hosts file, where is a display number that may be used to limit X window connections. Add the list of authorized X clients to the file.