Vulnerability Discussion
Misuse of the reboot command may cause availability issues for the system.
Check
Verify that RHEL 9 is configured to audit the execution of the "reboot" command with the following command:
$ sudo auditctl -l | grep reboot
-a always,exit -F path=/usr/sbin/reboot -F perm=x -F auid>=1000 -F auid!=unset -k privileged-reboot
If the command does not return a line, or the line is commented out, this is a finding.
Fix
Configure the audit system to generate an audit event for any successful/unsuccessful uses of the "reboot" command by adding or updating the following rule in the "/etc/audit/rules.d/audit.rules" file:
-a always,exit -F path=/usr/sbin/reboot -F perm=x -F auid>=1000 -F auid!=unset -k privileged-reboot
The audit daemon must be restarted for the changes to take effect.
$ sudo service auditd restart