Information
Securing SMTP involves requiring users to authenticate to the SMTP server before relaying messages, setting operator permissions, and requiring TLS encryption. NOTE: Nessus did not perform this check as it requires manual verification that only required SMTP relays are listed in the Relay Restrictions list. NOTE: The Nessus Plugin Family 'SMTP Problems' contains many checks related to SMTP security and should be enabled in your scan policy.
NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.
Solution
Make sure 'computer relay restrictions' is set to your organization's security policy.