Title

RHEL 9 must prevent a user from overriding the Ctrl-Alt-Del sequence settings for the graphical user interface. (Cat II impact)

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 mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot.

Check Content

Verify that users cannot enable the Ctrl-Alt-Del sequence in the GNOME desktop with the following command: Note: This requirement assumes the use of the RHEL 9 default graphical user interface, the GNOME desktop environment. If the system does not have any graphical user interface installed, this requirement is Not Applicable. $ grep logout /etc/dconf/db/local.d/locks/* /org/gnome/settings-daemon/plugins/media-keys/logout If the output is not "/org/gnome/settings-daemon/plugins/media-keys/logout", the line is commented out, or the line is missing, this is a finding.

Fix Text

Configure RHEL 9 to disallow the user changing the Ctrl-Alt-Del sequence in the GNOME desktop. Create a database to container system-wide graphical user logon settings (if it does not already exist) with the following command: $ sudo touch /etc/dconf/db/local.d/locks/session Add the following line to the session locks file to prevent nonprivileged users from modifying the Ctrl-Alt-Del setting: /org/gnome/settings-daemon/plugins/media-keys/logout Run the following command to update the database: $ sudo dconf update

Additional Identifiers

Rule ID: SV-258032r926083_rule

Vulnerability ID: V-258032

Group Title: SRG-OS-000480-GPOS-00227

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