The Photon operating system must be configured to protect the Secure Shell (SSH) public host key from unauthorized modification.

If a public host key file is modified by an unauthorized user, the SSH service may be compromised.

At the command line, run the following command:

# stat -c "%n permissions are %a and owned by %U:%G" /etc/ssh/*key.pub

Example result:

/etc/ssh/ssh_host_dsa_key.pub permissions are 644 and owned by root:root /etc/ssh/ssh_host_ecdsa_key.pub permissions are 644 and owned by root:root /etc/ssh/ssh_host_ed25519_key.pub permissions are 644 and owned by root:root /etc/ssh/ssh_host_rsa_key.pub permissions are 644 and owned by root:root

If any "key.pub" file listed is not owned by root or not group owned by root or does not have permissions of "0644", this is a finding.

At the command line, run the following commands for each returned file:

# chmod 644 <file>
# chown root:root <file>
# systemctl restart sshd.service