The graphical display manager must not be the default target on RHEL 9 unless approved.

Unnecessary service packages must not be installed 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.

Verify that RHEL 9 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.

Document the requirement for a graphical user interface with the ISSO or set the default target to multi-user with the following command:

$ sudo systemctl set-default multi-user.target