windows_default_group_policy_object_modified_with_gpme.yml

name: Windows Default Group Policy Object Modified with GPME
id: eaf688b3-bb8f-454d-b105-920a862cd8cb
version: 1
date: '2023-04-24'
author: Mauricio Velazco, Splunk
status: production
type: TTP
data_source:
- Sysmon EventID 1
description: The following analytic leverages the Endpoint datamodel to identify the
  potential edition of a default Group Policy Object. A fresh installation of an Active
  Directory network will typically contain two default group policy objects `Default
  Domain Controllers Policy` and `Default Domain Policy`. The default domain controllers
  policy is used to enforce and set policies to all the domain controllers within
  the domain environment. The default domain policy is linked to all users and computers
  by default. An adversary who has obtained privileged access to an Active Directory
  network may modify the default group policy objects to obtain further access, deploy
  persistence or execute malware across a large number of hosts. Security teams should
  monitor the edition of the default GPOs.
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where Processes.process_name=mmc.exe
  (Processes.process =*gpme.msc*) AND (Processes.process = "*31B2F340-016D-11D2-945F-00C04FB984F9*"
  OR Processes.process = "*6AC1786C-016F-11D2-945F-00C04fB984F9*"  ) by Processes.dest
  Processes.user Processes.parent_process_name Processes.process_name Processes.process
  Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)`
  | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_default_group_policy_object_modified_with_gpme_filter`'
how_to_implement: The detection is based on data that originates from Endpoint Detection
  and Response (EDR) agents. These agents are designed to provide security-related
  telemetry from the endpoints where the agent is installed. To implement this search,
  you must ingest logs that contain the process GUID, process name, and parent process.
  Additionally, you must ingest complete command-line executions. These logs must
  be processed using the appropriate Splunk Technology Add-ons that are specific to
  the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint`
  data model. Use the Splunk Common Information Model (CIM) to normalize the field
  names and speed up the data modeling process.
known_false_positives: The default Group Policy Objects within an AD network may be
  legitimately updated for administrative operations, filter as needed.
references:
- https://attack.mitre.org/techniques/T1484/
- https://attack.mitre.org/techniques/T1484/001
- https://www.trustedsec.com/blog/weaponizing-group-policy-objects-access/
- https://adsecurity.org/?p=2716
- https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/dn265969(v=ws.11)
tags:
  analytic_story:
  - Active Directory Privilege Escalation
  - Sneaky Active Directory Persistence Tricks
  asset_type: Endpoint
  confidence: 50
  impact: 100
  message: A default group policy object was opened with Group Policy Manage Editor
    on $dest$
  mitre_attack_id:
  - T1484
  - T1484.001
  observable:
  - name: dest
    type: Hostname
    role:
    - Victim
  - name: parent_process_name
    type: Process
    role:
    - Parent Process
  - name: process_name
    type: Process
    role:
    - Child Process
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Processes.dest
  - Processes.user
  - Processes.parent_process_name
  - Processes.parent_process
  - Processes.original_file_name
  - Processes.process_name
  - Processes.process
  - Processes.process_id
  - Processes.parent_process_path
  - Processes.process_path
  - Processes.parent_process_id
  risk_score: 50
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1484.001/default_domain_policy_modified/windows-security.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: xmlwineventlog