Vulnerability Discussion
The "/etc/passwd" file contains information about the users that are configured on the system. Protection of this file is critical for system security.
Check
Verify the group ownership of the "/etc/passwd" file with the following command:
$ sudo stat -c "%G %n" /etc/passwd
root /etc/passwd
If "/etc/passwd" file does not have a group owner of "root", this is a finding.
Fix
Change the group of the file /etc/passwd to root by running the following command:
$ sudo chgrp root /etc/passwd