Detection rules › Splunk
Windows Large Number of Computer Service Tickets Requested
The following analytic detects a high volume of Kerberos service ticket requests, specifically more than 30, from a single source within a 5-minute window. It leverages Event ID 4769, which logs when a Kerberos service ticket is requested, focusing on requests with computer names as the Service Name. This behavior is significant as it may indicate malicious activities such as lateral movement, malware staging, or reconnaissance. If confirmed malicious, an attacker could gain unauthorized access to multiple endpoints, potentially compromising the entire network.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access | T1078 Valid Accounts |
| Persistence | T1078 Valid Accounts |
| Privilege Escalation | T1078 Valid Accounts |
| Defense Evasion | T1078 Valid Accounts |
| Discovery | T1135 Network Share Discovery |
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Security-Auditing | 4769 | A Kerberos service ticket was requested. |
Stages and Predicates
Stage 1: search
search EventCode=4769 ServiceName="*$" TargetUserName!="*$"
Stage 2: bucket
bucket span=5m _time
Stage 3: stats
stats dc(ServiceName) AS unique_targets, … AS host_targets, … AS dest BY _time, IpAddress, TargetUserName
Stage 4: where
where unique_targets>30
Stage 5: 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.
| Field | Kind | Values |
|---|---|---|
EventCode | eq |
|
ServiceName | eq |
|
TargetUserName | ne |
|
unique_targets | gt |
|
Neighbors
Broader alternatives (more inclusive than this rule)
These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.
- Suspicious Kerberos Service Ticket Request (drops 2 filters this rule applies)