Vulnerability Discussion
Service configuration files enable or disable features of their respective services, which if configured incorrectly, can lead to insecure and vulnerable configurations. Therefore, service configuration files must be owned by the correct group to prevent unauthorized changes.
Check
Verify the group ownership of the "/etc/ssh/sshd_config" file with the following command:
$ ls -al /etc/ssh/sshd_config
rw-------. 1 root root 3669 Feb 22 11:34 /etc/ssh/sshd_config
If the "/etc/ssh/sshd_config" file does not have a group owner of "root", this is a finding.
Fix
Configure the "/etc/ssh/sshd_config" file to be group-owned by root with the following command:
$ sudo chgrp root /etc/ssh/sshd_config