Windows DNS Query with Kerberos Coercion Signature via DNS Object SPN Spoofing

Alerts on Windows DNS queries containing a base64-like credential target signature linked to Kerberos coercion via DNS spoofing.

FreeReviewedSigma · High · v2
Product
windows
Category
dns_query
Author
Swachchhanda Shrawan Poudel (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2025-06-20
Updated
2026-07-31
title: Windows DNS Query with Kerberos Coercion Signature via DNS Object SPN Spoofing
id: 6dabf949-0bd7-44c0-96fa-63d2c23f9a65
related:
  - id: b07e58cf-cacc-4135-8473-ccb2eba63dd2
    type: similar
  - id: 5588576c-5898-4fac-bcdd-7475a60e8f43
    type: similar
  - id: e7a21b5f-d8c4-4ae5-b8d9-93c5d3f28e1c
    type: derived
status: experimental
description: This rule matches Windows DNS queries whose QueryName contains a base64-derived pattern consistent with a Kerberos coercion signature tied to marshaled CREDENTIAL_TARGET_INFORMATION data. Such behavior matters because attackers can use DNS object/spoofing techniques to redirect or coerce authentication attempts toward attacker-controlled targets. It relies on telemetry that logs Windows DNS query names (QueryName) and checks for the specific substring markers present in the detection condition.
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
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/dns_query/dns_query_win_kerberos_coercion_via_dns_object_spoofing.yml
author: Swachchhanda Shrawan Poudel (Nextron Systems), Huntrule Team
date: 2025-06-20
tags:
  - attack.collection
  - attack.credential-access
  - attack.persistence
  - attack.privilege-escalation
  - attack.t1557.001
  - attack.t1187
logsource:
  product: windows
  category: dns_query
detection:
  selection:
    QueryName|contains|all:
      - UWhRCA
      - BAAAA
  condition: selection
falsepositives:
  - Unknown
level: high
license: DRL-1.1