Information
A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, the GNOME desktop can be configured to identify when a user's session has idled and take action to initiate the session lock. As such, users should not be allowed to change session settings.
Satisfies: SRG-OS-000029-GPOS-00010, SRG-OS-000031-GPOS-00012
Solution
Configure RHEL 9 to prevent a user from overriding settings for graphical user interfaces.
Create a database to contain the system-wide screensaver settings (if it does not already exist) with the following command:
Note: The example below is using the database 'local' for the system, so if the system is using another database in '/etc/dconf/profile/user', the file should be created under the appropriate subdirectory.
$ sudo touch /etc/dconf/db/local.d/locks/session
Add the following setting to prevent nonprivileged users from modifying it:
/org/gnome/desktop/session/idle-delay