Detection rules › Splunk
PetitPotam Suspicious Kerberos TGT Request
The following analytic detects a suspicious Kerberos Ticket Granting Ticket (TGT) request, identified by Event Code 4768. This detection leverages Windows Security Event Logs to identify TGT requests with unusual fields, which may indicate the use of tools like Rubeus following the exploitation of CVE-2021-36942 (PetitPotam). This activity is significant as it can signal an attacker leveraging a compromised certificate to request Kerberos tickets, potentially leading to unauthorized access. If confirmed malicious, this could allow attackers to escalate privileges and persist within the environment, posing a severe security risk.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Credential Access | T1003 OS Credential Dumping |
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Security-Auditing | 4768 | A Kerberos authentication ticket (TGT) was requested. |
Stages and Predicates
Stage 1: search
search CertThumbprint!="" EventCode=4768 TargetUserName="*$" src!="::1"
Stage 2: stats
stats BY dest, TargetUserName, src, action
Stage 3: search
search
Stage 4: search
search
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 |
|---|---|---|
CertThumbprint | ne |
|
EventCode | eq |
|
TargetUserName | eq |
|
src | ne |
|