Detection rules › Splunk

Windows Kerberos Coercion via DNS

Author
Raven Tait, Splunk
Source
upstream

Detects DNS-based Kerberos coercion attacks where adversaries inject marshaled credential structures into DNS records to spoof SPNs and redirect authentication such as in CVE-2025-33073. This detection leverages Windows Security Event Codes 5136, 5137, 4662, looking for DNS events with specific CREDENTIAL_TARGET_INFORMATION entries.

MITRE ATT&CK coverage

TacticTechniques
Credential AccessT1187 Forced Authentication, T1557.001 Adversary-in-the-Middle: LLMNR/NBT-NS Poisoning and SMB Relay
CollectionT1557.001 Adversary-in-the-Middle: LLMNR/NBT-NS Poisoning and SMB Relay
Command & ControlT1071.004 Application Layer Protocol: DNS

Event coverage

ProviderEvent IDTitle
Security-Auditing4662An operation was performed on an object.
Security-Auditing5136A directory service object was modified.
Security-Auditing5137A directory service object was created.

Stages and Predicates

Stage 1: search

search (((EventCode="5136" OR EventCode="5137") ObjectClass="dnsNode" ObjectDN="*1UWhRCA*" ObjectDN="*AAAAA*" ObjectDN="*YBAAAA*") OR (AdditionalInfo="*1UWhRCA*" AdditionalInfo="*AAAAA*" AdditionalInfo="*YBAAAA*" EventCode="4662"))

Stage 2: eval

eval ... using (AdditionalInfo2, ObjectGUID)

Stage 3: eval

eval ... using (Caller_User_Name, SubjectUserName)

Stage 4: stats

stats BY Object

Stage 5: search

search

Stage 6: search

search

Stage 7: search

search `macro`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
AdditionalInfoeq
  • "*1UWhRCA*"
  • "*AAAAA*"
  • "*YBAAAA*"
EventCodeeq
  • "4662"
  • "5136"
  • "5137"
ObjectClasseq
  • "dnsNode" corpus 2 (splunk 2)
ObjectDNeq
  • "*1UWhRCA*"
  • "*AAAAA*"
  • "*YBAAAA*"

Neighbors

Often fire together

Rules that target events appearing in the same incident timelines. They pattern-match on adjacent steps of the same TTP, so an alert from one is often paired with alerts from these. Useful for triage context and for assembling chained-detection rules.

Share event IDs (chain-detection candidates)

Rules that observe the same Windows event-ID pairs as this one. If you're authoring a multi-stage / sequence rule that spans these events, these are the existing detections that already cover one or both endpoints.