Vulnerability Discussion

Using interactive or recovery boot, the console user could disable auditing, firewalls, or other services, weakening system security.

Check

Verify that GRUB 2 is configured to disable interactive boot.

Check that the current GRUB 2 configuration disables the ability of systemd to spawn an interactive boot process with the following command:

$ sudo grubby --info=ALL | grep args | grep 'systemd.confirm_spawn'

If any output is returned, this is a finding.

Fix

Configure RHEL 9 to allocate sufficient audit_backlog_limit to disable the ability of systemd to spawn an interactive boot process with the following command:

$ sudo grubby --update-kernel=ALL --remove-args="systemd.confirm_spawn"