AlmaLinux OS 9 must prevent a user from overriding the Ctrl-Alt-Del sequence settings for the graphical user interface.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-269188	SRG-OS-000480-GPOS-00227	ALMA-09-012340	SV-269188r1050070_rule	2025-02-20	1

Description
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.

ℹ️ Check
Note: This requirement assumes the use of the AlmaLinux OS 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. Verify that users cannot enable the Ctrl-Alt-Del sequence in the GNOME desktop with the following command: $ 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.

ℹ️ Check

Note: This requirement assumes the use of the AlmaLinux OS 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. Verify that users cannot enable the Ctrl-Alt-Del sequence in the GNOME desktop with the following command: $ 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
Configure AlmaLinux OS 9 to disallow the user changing the Ctrl-Alt-Del sequence in the GNOME desktop. Create a database to container systemwide graphical user logon settings (if it does not already exist) with the following command: $ 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: $ dconf update

✔️ Fix

Configure AlmaLinux OS 9 to disallow the user changing the Ctrl-Alt-Del sequence in the GNOME desktop. Create a database to container systemwide graphical user logon settings (if it does not already exist) with the following command: $ 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: $ dconf update