Active Directory Group Policy is a Windows management system that lets administrators centrally apply settings, restrictions, scripts, and security controls to users and computers in a domain. It is one of the main ways organizations enforce standards such as password policy, software deployment, firewall rules, and login behavior.
It matters in cyber security because anyone with sufficient domain privileges can use Group Policy to change many systems at once. Defenders rely on it to harden endpoints and reduce misconfiguration, but attackers who obtain domain-admin-level access can abuse it to disable defenses, push malicious commands, block services, or cause widespread disruption without dropping traditional malware. For this reason, Group Policy changes should be tightly controlled, logged, and reviewed for unexpected edits.