The rule "Expired or Revoked Driver Loaded" is designed to identify attempts to load drivers that have either expired or been revoked. This is significant as adversaries may exploit outdated drivers with known vulnerabilities to execute malicious code in kernel mode, or they may misuse revoked certificates for signing their malicious drivers. The detection employs an EQL (Event Query Language) query focused on Windows systems, specifically targeting the System process (PID 4). The detection criteria include checking for drivers (DLLs) where the code signature status indicates either an "errorExpired" or "errorRevoked" condition. If this detection occurs, it might indicate potential privilege escalation attempts or defense evasion strategies by attackers. The rule relies on data sourced from endpoint event libraries and is part of a larger framework for monitoring and response in Windows environments. Triage and analysis tasks associated with this detection include confirming the driver's signature status, investigating potential malicious origins, and assessing overall system integrity. False positives can occur due to legitimate software updates or necessary drivers from older hardware, necessitating careful validation of the context behind each alert.