Vulnerability Discussion

Failure to restrict system access to authenticated users negatively impacts operating system security.

Check

Verify the operating system does not allow a non-certificate trusted host SSH logon to the system.

Check for the value of the "HostbasedAuthentication" keyword with the following command:

# grep -i hostbasedauthentication /etc/ssh/sshd_config
HostbasedAuthentication no

If the "HostbasedAuthentication" keyword is not set to "no", is missing, or is commented out, this is a finding.

Fix

Configure the operating system not to allow a non-certificate trusted host SSH logon to the system.

Edit the "/etc/ssh/sshd_config" file to uncomment or add the line for "HostbasedAuthentication" keyword and set the value to "no":

HostbasedAuthentication no

The SSH service must be restarted for changes to take effect.