IT Best Practices Tip: nist_V-38613

Severity: medium

Short Description

The system must not permit root logins using remote access programs such as ssh.

Long Description

Permitting direct root login reduces auditable information about who ran privileged commands on the system and also allows direct attack attempts on root's password.

How to Check Correct Configuration

To determine how the SSH daemon's "PermitRootLogin" option is set, run the following command:

# grep -i PermitRootLogin /etc/ssh/sshd_config

If a line indicating "no" is returned, then the required value is set.
If the required value is not set, this is a finding.

How to Fix

The root user should never be allowed to log in to a system directly over a network. To disable root login via SSH, add or correct the following line in "/etc/ssh/sshd_config":

PermitRootLogin no