This article demonstrates a full GPO-abuse attack chain in the ignite.local lab where a low-privilege user with delegated edit rights on a domain-linked GPO is used to push malicious scheduled tasks and scripts to reach the Domain Controller. Using BloodHound to discover writable GPOs and tools like pyGPOAbuse, SharpGPOAbuse, and StandIn, the attacker creates persistent local administrators and interactive reverse shells, while defenders are advised to treat GPO write access as Tier 0 and monitor SYSVOL/LDAP for tampering. #pyGPOAbuse #SharpGPOAbuse
Keypoints
- A delegated “Edit settings, delete, modify security” permission on a domain-linked GPO enables domain-wide code execution, including on Domain Controllers.
- BloodHound enumeration reveals writable GPOs and the GUIDs needed to target SYSVOL policy files.
- pyGPOAbuse, SharpGPOAbuse, and StandIn can inject scheduled tasks, startup scripts, or Restricted Groups to create local admins or launch reverse shells.
- Attacks can be executed from a Linux network foothold or a Windows foothold, yielding SYSTEM or interactive administrator contexts.
- Mitigations include strict GPO DACL auditing, scoped GPO links, tiered administration, SYSVOL/LDAP monitoring, and LAPS to reduce the blast radius.
Read More: https://www.hackingarticles.in/gpo-abuse-exploiting-vulnerable-group-policy-objects/