name: GetAdComputer with PowerShell Script Block
id: a9a1da02-8e27-4bf7-a348-f4389c9da487
version: 3
date: '2022-05-02'
author: Mauricio Velazco, Splunk
status: production
type: Hunting
description: The following analytic utilizes PowerShell Script Block Logging (EventCode=4104)
  to identify the execution of the `Get-AdGroup` commandlet. The `Get-AdGroup` commandlet
  is used to return a list of all domain computers. Red Teams and adversaries may
  leverage this commandlet to enumerate domain computers for situational awareness
  and Active Directory Discovery.
data_source:
- Powershell 4104
search: '`powershell` EventCode=4104 (ScriptBlockText = "*Get-AdComputer*") | stats
  count min(_time) as firstTime max(_time) as lastTime by Opcode Computer UserID EventCode
  ScriptBlockText | `security_content_ctime(firstTime)` | `getadcomputer_with_powershell_script_block_filter`'
how_to_implement: To successfully implement this analytic, you will need to enable
  PowerShell Script Block Logging on some or all endpoints. Additional setup here
  https://docs.splunk.com/Documentation/UBA/5.0.4.1/GetDataIn/AddPowerShell#Configure_module_logging_for_PowerShell.
known_false_positives: Administrators or power users may use this PowerShell commandlet
  for troubleshooting.
references:
- https://attack.mitre.org/techniques/T1018/
- https://docs.microsoft.com/en-us/powershell/module/activedirectory/get-adgroup?view=windowsserver2019-ps
tags:
  analytic_story:
  - Active Directory Discovery
  - CISA AA22-320A
  asset_type: Endpoint
  confidence: 50
  impact: 30
  message: Remote system discovery enumeration on $Computer$ by $UserID$
  mitre_attack_id:
  - T1018
  observable:
  - name: Computer
    type: Endpoint
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - ScriptBlockText
  - Opcode
  - Computer
  - UserID
  - EventCode
  risk_score: 15
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1059.001/powershell_script_block_logging/sbl_xml.log
    source: XmlWinEventLog:Microsoft-Windows-PowerShell/Operational
    sourcetype: xmlwineventlog