An X server must have none of the following options enabled: -ac, -core (except for debugging purposes), or -nolock.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-1022	GEN000000-LNX00380	SV-37217r2_rule		Medium

Description
These options will detract from the security of the Xwindows system.

STIG	Date
Red Hat Enterprise Linux 5 Security Technical Implementation Guide	2016-06-01

Details

Check Text ( C-35904r2_chk )
If the "xorg-x11-server-Xorg" package is not installed, this is not applicable. Verify the options of the running Xwindows server are correct. Procedure: Get the running xserver information # ps -ef \|grep X If the response contains /usr/bin/Xorg:0 /usr/bin/Xorg:0 -br -audit 0 -auth /var/gdm/:0.Xauth -nolisten tcp vt7 this is indicative of Xorg starting through gdm. This is the default window manager on RHEL. If the "-ac" option is found, this is a finding. If the "-core" option is found, this is a finding. If the "-nolock" option is found, this is a finding. If the response to the grep contains X:0 /usr/bin/X:0 Examine the X:0 line: If the "-ac" option is found, this is a finding. If the "-core" option is found, this is a finding. If the "-nolock" option is found, this is a finding.

Check Text ( C-35904r2_chk )

If the "xorg-x11-server-Xorg" package is not installed, this is not applicable.

Verify the options of the running Xwindows server are correct.

Procedure:

Get the running xserver information

# ps -ef |grep X

If the response contains /usr/bin/Xorg:0

/usr/bin/Xorg:0 -br -audit 0 -auth /var/gdm/:0.Xauth -nolisten tcp vt7

this is indicative of Xorg starting through gdm. This is the default window manager on RHEL.

If the "-ac" option is found, this is a finding.
If the "-core" option is found, this is a finding.
If the "-nolock" option is found, this is a finding.

If the response to the grep contains X:0

/usr/bin/X:0

Examine the X:0 line:

If the "-ac" option is found, this is a finding.
If the "-core" option is found, this is a finding.
If the "-nolock" option is found, this is a finding.

Fix Text (F-31162r1_fix)
Disable the unwanted options: Procedure: For gdm: Remove the -ac, -core and -nolock options by creating a "command" entry in the /etc/gdm/custom.conf file with the options removed. For Xwindows started by xinit: Create or modify the .xserverrc script in the users home directory to remove the -ac, -core and -nolock options from the exec /usr/bin/X command.