The TOSS 5 /etc/shadow file must have mode 0000 to prevent unauthorized access.

The "/etc/shadow" file contains the list of local system accounts and stores password hashes. Protecting this file is critical for system security. Failure to give ownership of this file to root provides the designated owner with access to sensitive information, which could weaken the system security posture.

Verify the "/etc/shadow" file has mode "0000" using the following command:

$ sudo stat -c "%a %n" /etc/shadow

0 /etc/shadow

If a value of "0" is not returned, this is a finding.

Change the mode of the file "/etc/shadow" to "0000" using the following command:

$ sudo chmod 0000 /etc/shadow