This rule detects attempts to log in using the default username associated with the DiagTrackEoP Proof of Concept (POC) tool. Specifically, it identifies logon events (EventID 4624) where the logon type is 9 (New credentials) and the target outbound username is 'thisisnotvaliduser'. This username is a known default value for the DiagTrackEoP POC, and its usage in a logon event raises a flag for potential unauthorized access or privilege escalation attempts. The rule aims to prevent the exploitation of this default credential that might be overlooked during security assessments.