Sigma rule: Suspicious DNS Query Indicating Kerberos Coercion via DNS Object SPN Spoofing
A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-209d45a9f91f, updated 2025-06-20T00:00:00.000Z.
Rule
- Title
- Suspicious DNS Query Indicating Kerberos Coercion via DNS Object SPN Spoofing
- Status
- experimental
- Level
- high
- Author
- Swachchhanda Shrawan Poudel (Nextron Systems)
- Date
- 2025-06-20
- File
- rules/windows/dns_query/dns_query_win_kerberos_coercion_via_dns_object_spoofing.yml
- Commit
- ccbb0369507f796db0b0ae6854c8a2be471b9d84
Detects DNS queries containing patterns associated with Kerberos coercion attacks via DNS object spoofing.
The pattern "1UWhRCAAAAA..BAAAA" is a base64-encoded signature that corresponds to a marshaled CREDENTIAL_TARGET_INFORMATION structure.
Attackers can use this technique to coerce authentication from victim systems to attacker-controlled hosts.
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.
Log source
- product
- windows
- category
- dns_query
Detection
selection:
QueryName|contains|all:
- 'UWhRCA'
- 'BAAAA'
condition: selectionFalse positives (as the rule lists them)
- Unknown
Tags
- attack.collection
- attack.credential-access
- attack.persistence
- attack.privilege-escalation
- attack.t1557.001
- attack.t1187
MITRE ATT&CK ids this rule names
Related rules
References
- https://www.synacktiv.com/publications/ntlm-reflection-is-dead-long-live-ntlm-reflection-an-in-depth-analysis-of-cve-2025
- https://googleprojectzero.blogspot.com/2021/10/using-kerberos-for-authentication-relay.html
Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/dns_query/dns_query_win_kerberos_coercion_via_dns_object_spoofing.yml
Sources and licences
SigmaHQ
"Suspicious DNS Query Indicating Kerberos Coercion via DNS Object SPN Spoofing" by Swachchhanda Shrawan Poudel (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/dns_query/dns_query_win_kerberos_coercion_via_dns_object_spoofing.yml.
Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License
Cite this page
Dragons Eye Ransomware Tracker, "Sigma rule: Suspicious DNS Query Indicating Kerberos Coercion via DNS Object SPN Spoofing",
entity page, dataset version ref-209d45a9f91f, updated 2025-06-20T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/e7a21b5f-d8c4-4ae5-b8d9-93c5d3f28e1c (accessed 2026-11-03).
Underlying source: SigmaHQ rule e7a21b5f-d8c4-4ae5-b8d9-93c5d3f28e1c, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.
Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.