ID | Technique | Tactic |
---|---|---|
T1484 | Domain or Tenant Policy Modification | Defense Evasion |
T1484.001 | Group Policy Modification | Privilege Escalation |
T1078.002 | Domain Accounts | Defense Evasion |
Detection: Windows Group Policy Object Created
Description
The following analytic detects the creation of a new Group Policy Object (GPO) by leveraging Event IDs 5136 and 5137. This detection uses directory service change events to identify when a new GPO is created. Monitoring GPO creation is crucial as adversaries can exploit GPOs to escalate privileges or deploy malware across an Active Directory network. If confirmed malicious, this activity could allow attackers to control system configurations, deploy ransomware, or propagate malware, leading to widespread compromise and significant operational disruption.
Search
1`wineventlog_security` EventCode=5137 OR (EventCode=5136 AttributeValue!="New Group Policy Object" AND (AttributeLDAPDisplayName=displayName OR AttributeLDAPDisplayName=gPCFileSysPath) ) ObjectClass=groupPolicyContainer
2| stats values(AttributeValue) as details values(SubjectUserSid) as User values(ObjectDN) as ObjectDN by ObjectGUID Computer
3| eval GPO_Name = mvindex(details, 0)
4| eval GPO_Path = mvindex(details, 1)
5| fields - details
6| `windows_group_policy_object_created_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
Windows Event Log Security 5136 | Windows | 'xmlwineventlog' |
'XmlWinEventLog:Security' |
N/A |
Macros Used
Name | Value |
---|---|
wineventlog_security | eventtype=wineventlog_security OR Channel=security OR source=XmlWinEventLog:Security |
windows_group_policy_object_created_filter | search * |
windows_group_policy_object_created_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
Default Configuration
This detection is configured by default in Splunk Enterprise Security to run with the following settings:
Setting | Value |
---|---|
Disabled | true |
Cron Schedule | 0 * * * * |
Earliest Time | -70m@m |
Latest Time | -10m@m |
Schedule Window | auto |
Creates Notable | Yes |
Rule Title | %name% |
Rule Description | %description% |
Notable Event Fields | user, dest |
Creates Risk Event | True |
Implementation
To successfully implement this search, the Advanced Security Audit policy setting Audit Directory Service Changes
within DS Access
needs to be enabled. Furthermore, the appropriate system access control lists (SACL) need to be created as the used events are not logged by default. A good guide to accomplish this can be found here https://jgspiers.com/audit-group-policy-changes/.
Known False Positives
Group Policy Objects are created as part of regular administrative operations, filter as needed.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
A new group policy objected was created by $User$ | 40 | 80 | 50 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | XmlWinEventLog:Security |
XmlWinEventLog |
Integration | ✅ Passing | Dataset | XmlWinEventLog:Security |
XmlWinEventLog |
Replay any dataset to Splunk Enterprise by using our replay.py
tool or the UI.
Alternatively you can replay a dataset into a Splunk Attack Range
Source: GitHub | Version: 3