This detection rule identifies changes to the Windows Registry that indicate Windows Defender has been disabled, which is a common tactic employed by threat actors to bypass security measures. The rule operates by monitoring specific registry paths associated with Windows Defender settings. Any modifications to settings that disable the anti-spyware feature or change the service startup configuration to manual trigger alerts. The investigation guide outlines steps such as reviewing the process execution chain for unknown processes, validating if the modifications are administrative activities, and contacting the account owner to ascertain the legitimacy of actions taken. Additionally, the rule advises on handling false positives and offers a structured incident response protocol, which includes isolating affected hosts, restoring Windows Defender service configurations, and conducting thorough malware scans. By analyzing these behaviors, analysts can better identify potential compromises and security incidents involving the manipulation of essential protective measures in Windows environments.