Posture check · Delegation and Kerberos
Account can add a service name to an account that has none (T1558.003)
An account can add a service name to this account. That makes this account's password crackable offline from a Kerberos ticket.
Why it matters
Anyone who takes over the writing account can request a ticket for this account and crack its password.
How GraphnAI finds it
It runs after every sync, on each connected domain or tenant on its own. It applies to Active Directory.
It reads:
- The directory attributes
objectSid,userAccountControl,accountEnabledandservicePrincipalName - Directory permissions (access control entries)
- The privilege tier classification
Tiered Fidelity™ level: Constrained
Every finding from this check carries the Constrained level.
- TheoreticalConfigured in the directory. Nothing else checked.
- ConstrainedThis checkA constraint on it has been checked.
- ValidatedTelemetry has seen it in use.
How Select Fire™ fixes it
How to fix it
Remove the permission to change service names on this account from accounts that don't need it.
What Select Fire changes
Select Fire opens from the finding and simulates each change on your live graph before anything changes in your directory.
- Remove the permissionSemi-Auto: you authorize each change. Full-Auto never runs it.
The listed accounts can no longer change service names on this account. A tool that registers service names through one of them stops working. You can undo the change.
By hand: Remove the permission to change service names on this account from accounts outside Tier 0.
If someone uses it
This detection rule raises an alert when the attack this exposure invites shows up in your domain controllers' events.
Related checks
MITRE ATT&CK® technique names and MITRE D3FEND™ technique labels: © The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. ATT&CK® is a registered trademark and D3FEND™ a trademark of The MITRE Corporation.
See it on your own directory.
The Public Preview is free for 30 days from your first sync, on your own server.