The OL 8 SSH private host key files must have mode "0640" or less permissive.

STIG ID: OL08-00-010490 |  SRG: SRG-OS-000480-GPOS-00227 |  Severity: medium |  CCI:  | Vulnerability Id: V-248602

Vulnerability Discussion

If an unauthorized user obtains the private SSH host key file, the host could be impersonated.

Check

Configure the mode of SSH private host key files under "/etc/ssh" to "0640" with the following command:

$ sudo chmod 0640 /etc/ssh/ssh_host*key

The SSH daemon must be restarted for the changes to take effect. To restart the SSH daemon, run the following command:

$ sudo systemctl restart sshd.service

Fix

Verify the SSH private host key files have mode "0640" or less permissive with the following command:

$ sudo ls -alL /etc/ssh/ssh_host*key

-rw-r----- 1 root wheel 668 Nov 28 06:43 ssh_host_dsa_key
-rw-r----- 1 root wheel 582 Nov 28 06:43 ssh_host_key
-rw-r----- 1 root wheel 887 Nov 28 06:43 ssh_host_rsa_key

If any private host key file has a mode more permissive than "0640", this is a finding.