An attacker with high privileges can obtain all the ingredients for generating the password of any gMSA in the domain at any time with two steps:
- Retrieve several attributes from the KDS root key in the domain
- Use the GoldenGMSA tool to generate the password of any gMSA associated with the key, without a privileged account.
Introducing the Golden GMSA Attack | Semperis
Or Yair, Security Researcher at SafeBreach Labs (Breach and Attack Simulation Platforms | New Solutions (safebreach.com)) explains why GMSAs present such a threat.