Title

The x86 Ctrl-Alt-Delete key sequence in RHEL 8 must be disabled if a graphical user interface is installed. (Cat I impact)

Discussion

A locally logged-on user, who presses Ctrl-Alt-Delete, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of a mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot. In a graphical user environment, risk of unintentional reboot from the Ctrl-Alt-Delete sequence is reduced because the user will be prompted before any action is taken.

Check Content

Verify RHEL 8 is not configured to reboot the system when Ctrl-Alt-Delete is pressed when using a graphical user interface with the following command: This requirement assumes the use of the RHEL 8 default graphical user interface, Gnome Shell. If the system does not have any graphical user interface installed, this requirement is Not Applicable. $ sudo grep logout /etc/dconf/db/local.d/* logout='' If the "logout" key is bound to an action, is commented out, or is missing, this is a finding.

Fix Text

Configure the system to disable the Ctrl-Alt-Delete sequence when using a graphical user interface by creating or editing the /etc/dconf/db/local.d/00-disable-CAD file. Add the setting to disable the Ctrl-Alt-Delete sequence for a graphical user interface: [org/gnome/settings-daemon/plugins/media-keys] logout='' Note: The value above is set to two single quotations. Then update the dconf settings: $ sudo dconf update

Additional Identifiers

Rule ID: SV-230530r1017290_rule

Vulnerability ID: V-230530

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

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.