Kerberos TGT Request Using RC4 Encryption
The following analytic detects a Kerberos Ticket Granting Ticket (TGT) request using RC4-HMAC encryption (type 0x17) by leveraging Event 4768. This encryption type is outdated and its presence may indicate an…
Description
The following analytic detects a Kerberos Ticket Granting Ticket (TGT) request using RC4-HMAC encryption (type 0x17) by leveraging Event 4768. This encryption type is outdated and its presence may indicate an OverPass The Hash attack. Monitoring this activity is crucial as it can signify credential theft, allowing adversaries to authenticate to the Kerberos Distribution Center (KDC) using a stolen NTLM hash. If confirmed malicious, this could enable unauthorized access to systems and resources, potentially leading to lateral movement and further compromise within the network.
Detection logic
Detection requirements
- Platform
- ContainersIaaSIdentity ProviderLinuxOffice SuiteSaaSWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- windows_event_log_security_4768
Known benign triggers
- Based on Microsoft documentation, legacy systems or applications will use RC4-HMAC as the default encryption for TGT requests. Specifically, systems before Windows Server 2008 and Windows Vista. Newer systems will use AES128 or AES256.
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 |
|---|---|
| docs.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4768 | Only this detection cites it |
| stealthbits.com/blog/how-to-detect-overpass-the-hash-attacks/ | 2 |
| www.thehacker.recipes/ad/movement/kerberos/ptk | 2 |
From the source
- At source
- Open at source
- Upstream identifier
- 18916468-9c04-11ec-bdc6-acde48001122
- Tagged by the source as
- Active Directory Kerberos AttacksScattered Lapsus$ HuntersEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1