Detection rules › Splunk

Get WMIObject Group Discovery with Script Block Logging

Status
production
Group by
Guid, Name, Opcode, Path, ScriptBlockId, ScriptBlockText, dest, process_id, signature, signature_id, user_id, vendor_product
Author
Michael Haag, Splunk
Source
github.com/splunk/security_content

The following analytic detects the execution of the Get-WMIObject Win32_Group command using PowerShell Script Block Logging (EventCode=4104). This method captures the full command sent to PowerShell, allowing for detailed analysis. Identifying group information on an endpoint is not inherently malicious but can be suspicious based on context such as time, endpoint, and user. This activity is significant as it may indicate reconnaissance efforts by an attacker. If confirmed malicious, it could lead to further enumeration and potential lateral movement within the network.

MITRE ATT&CK coverage

Event coverage

Rule body splunk

name: Get WMIObject Group Discovery with Script Block Logging
id: 69df7f7c-155d-11ec-a055-acde48001122
version: 11
creation_date: '2021-09-14'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: Hunting
description: The following analytic detects the execution of the `Get-WMIObject Win32_Group` command using PowerShell Script Block Logging (EventCode=4104). This method captures the full command sent to PowerShell, allowing for detailed analysis. Identifying group information on an endpoint is not inherently malicious but can be suspicious based on context such as time, endpoint, and user. This activity is significant as it may indicate reconnaissance efforts by an attacker. If confirmed malicious, it could lead to further enumeration and potential lateral movement within the network.
data_source:
    - Powershell Script Block Logging 4104
search: |-
    `powershell` EventCode=4104 ScriptBlockText = "*Get-WMIObject*" AND ScriptBlockText = "*Win32_Group*"
      | fillnull
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY dest signature signature_id
           user_id vendor_product EventID
           Guid Opcode Name
           Path ProcessID ScriptBlockId
           ScriptBlockText
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `get_wmiobject_group_discovery_with_script_block_logging_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://help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba.
known_false_positives: False positives may be present. Tune as needed.
references:
    - https://www.splunk.com/en_us/blog/security/powershell-detections-threat-research-release-august-2021.html
    - https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1069.001/T1069.001.md
    - https://help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba.
    - https://blog.palantir.com/tampering-with-windows-event-tracing-background-offense-and-defense-4be7ac62ac63
    - https://static1.squarespace.com/static/552092d5e4b0661088167e5c/t/59c1814829f18782e24f1fe2/1505853768977/Windows+PowerShell+Logging+Cheat+Sheet+ver+Sept+2017+v2.1.pdf
    - https://www.crowdstrike.com/blog/investigating-powershell-command-and-script-logging/
analytic_story:
    - Active Directory Discovery
asset_type: Endpoint
mitre_attack_id:
    - T1069.001
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1069.001/atomic_red_team/windows-powershell-xml.log
          source: XmlWinEventLog:Microsoft-Windows-PowerShell/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

Stages and Predicates

Stage 1: search

`powershell` EventCode=4104 ScriptBlockText = "*Get-WMIObject*" AND ScriptBlockText = "*Win32_Group*"

Stage 2: fillnull

| fillnull

Stage 3: stats

| stats count min(_time) as firstTime max(_time) as lastTime
    BY dest signature signature_id
       user_id vendor_product EventID
       Guid Opcode Name
       Path ProcessID ScriptBlockId
       ScriptBlockText

Stage 4: search

| `security_content_ctime(firstTime)`

Stage 5: search

| `security_content_ctime(lastTime)`

Stage 6: search

| `get_wmiobject_group_discovery_with_script_block_logging_filter`

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.

FieldKindValues
EventCodeeq
  • 4104 corpus 268 (splunk 268)
ScriptBlockTexteq
  • "*Get-WMIObject*" corpus 7 (splunk 5, sigma 2)
  • "*Win32_Group*" corpus 2 (sigma 1, splunk 1)