SMTP unauthenticated 3rd-party mail relay (from no-domain address)
While your mailer rejects 3rd-party relay in some cases, it allows mail to be relayed if the client issues a "MAIL FROM:" command using an address with no domain. This could be a configuration error, or a bug in the mail server.
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center