Vulnerability Discussion
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.
Check
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 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.