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 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 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 remove the related packages with the following commands:

# rpm -e xorg-x11-server-common

# systemctl set-default multi-user.target