The graphical display manager must not be installed on TOSS unless approved.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-253103	SRG-OS-000480-GPOS-00227	TOSS-04-040610	SV-253103r991589_rule	2024-05-30	2

Description
Internet services that are not required for system or application processes must not be active to decrease the attack surface of the system. Graphical display managers have a long history of security vulnerabilities and must not be used, unless approved and documented.

ℹ️ Check
Verify that the system is configured to boot to the command line: $ systemctl get-default multi-user.target If the system default target is not set to "multi-user.target" and the Information System Security Officer (ISSO) lacks a documented requirement for a graphical user interface, this is a finding. Verify that a graphical user interface is not installed: $ rpm -qa \| grep xorg \| grep server Ask the System Administrator if use of a graphical user interface is an operational requirement. If the use of a graphical user interface on the system is not documented with the ISSO, this is a finding.

ℹ️ Check

Verify that the system is configured to boot to the command line: $ systemctl get-default multi-user.target If the system default target is not set to "multi-user.target" and the Information System Security Officer (ISSO) lacks a documented requirement for a graphical user interface, this is a finding. Verify that a graphical user interface is not installed: $ rpm -qa | grep xorg | grep server Ask the System Administrator if use of a graphical user interface is an operational requirement. If the use of a graphical user interface on the system is not documented with the ISSO, this is a finding.

✔️ Fix
Document the requirement for a graphical user interface with the ISSO or reinstall the operating system without the graphical user interface. If reinstallation is not feasible, then continue with the following procedure: Open an SSH session and enter the following commands: $ sudo systemctl set-default multi-user.target $ sudo yum remove xorg-x11-server-Xorg xorg-x11-server-common xorg-x11-server-utils xorg-x11-server-Xwayland A reboot is required for the changes to take effect.

✔️ Fix

Document the requirement for a graphical user interface with the ISSO or reinstall the operating system without the graphical user interface. If reinstallation is not feasible, then continue with the following procedure: Open an SSH session and enter the following commands: $ sudo systemctl set-default multi-user.target $ sudo yum remove xorg-x11-server-Xorg xorg-x11-server-common xorg-x11-server-utils xorg-x11-server-Xwayland A reboot is required for the changes to take effect.