Vulnerability Discussion

A locally logged-in user who presses Ctrl-Alt-Del when at the console can reboot the system. If accidentally pressed, as could happen in the case of a mixed operating system environment, this can create the risk of short-term loss of systems' availability due to unintentional reboot.

Check

Note: This requirement assumes the use of the RHEL 10 default graphical user interface, the GNOME desktop environment. If the system does not have any graphical user interface installed, this requirement is not applicable.

Verify RHEL 10 users cannot enable the Ctrl-Alt-Del sequence in the GNOME desktop:

$ gsettings writable org.gnome.settings-daemon.plugins.media-keys logout
false

If "logout" is writable and the result is "true", this is a finding.

If GNOME is configured to shut down when Ctrl-Alt-Del is pressed, this is a finding.

Fix

Configure RHEL 10 to disallow the user changing the Ctrl-Alt-Del sequence in the GNOME desktop.

Note: The example below is using the database "local" for the system. If the system is using another database in "/etc/dconf/profile/user", the file should be created under the appropriate subdirectory.

Update the "/etc/dconf/db/local.d/locks/session" file to prevent nonprivileged users from modifying the Ctrl-Alt-Del setting:

$ sudo vi /etc/dconf/db/local.d/locks/session

/org/gnome/settings-daemon/plugins/media-keys/logout

Run the following command to update the database:

$ sudo dconf update