Title

The Ubuntu Operating system must disable the x86 Ctrl-Alt-Delete key sequence. (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.

Check Content

Verify the Ubuntu operating system is not configured to reboot the system when Ctrl-Alt-Delete is pressed. Check that the "ctrl-alt-del.target" (otherwise also known as reboot.target) is not active with the following command: $ sudo systemctl status ctrl-alt-del.target ctrl-alt-del.target Loaded: masked (/dev/null; bad) Active: inactive (dead) If the "ctrl-alt-del.target" is not masked, this is a finding.

Fix Text

Configure the system to disable the Ctrl-Alt-Delete sequence for the command line with the following commands: $ sudo systemctl disable ctrl-alt-del.target $ sudo systemctl mask ctrl-alt-del.target And reload the daemon to take effect: $ sudo systemctl daemon-reload

Additional Identifiers

Rule ID: SV-219212r832928_rule

Vulnerability ID: V-219212

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

Expert Comments

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