Potential Kerberos Coercion by Spoofing SPNs via DNS Manipulation
Detects modifications to DNS records in Active Directory where the Distinguished Name (DN) contains a base64-encoded blob matching the pattern "1UWhRCAAAAA...BAAAA". This pattern corresponds to a marshaled…
Description
Detects modifications to DNS records in Active Directory where the Distinguished Name (DN) contains a base64-encoded blob matching the pattern "1UWhRCAAAAA...BAAAA". This pattern corresponds to a marshaled CREDENTIAL_TARGET_INFORMATION structure, commonly used in Kerberos coercion attacks. Adversaries may exploit this to coerce victim systems into authenticating to attacker-controlled hosts by spoofing SPNs via DNS. It is one of the strong indicators of a Kerberos coercion attack,. where adversaries manipulate DNS records to spoof Service Principal Names (SPNs) and redirect authentication requests like CVE-2025-33073. Please investigate the user account that made the changes, as it is likely a low-privileged account that has been compromised.
Detection logic
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| googleprojectzero.blogspot.com/2021/10/using-kerberos-for-authentication-relay.html | 9from 2 sources |
| www.synacktiv.com/publications/ntlm-reflection-is-dead-long-live-ntlm-reflection-an-in-depth-analysis-of-cve-2025 | 6from 2 sources |
From the source
- At source
- Open at source
- Upstream identifier
- b07e58cf-cacc-4135-8473-ccb2eba63dd2
- Tagged by the source as
- attack.collectionattack.credential-accessattack.persistenceattack.privilege-escalation
Licence
- Published under
- Detection Rule License 1.1Read the licence
- Attribution
- Required
Authorship
- Published
- Aug 26, 2026
- Version
- 1