Detection rules › Splunk

Get DomainUser with PowerShell Script Block

Status
production
Severity
medium
Group by
Guid, Name, Opcode, Path, ScriptBlockId, ScriptBlockText, dest, process_id, signature, signature_id, user_id, vendor_product
Author
Teoderick Contreras, Mauricio Velazco, Splunk
Source
github.com/splunk/security_content

The following analytic detects the execution of the Get-DomainUser cmdlet using PowerShell Script Block Logging (EventCode=4104). This cmdlet is part of PowerView, a tool often used for domain enumeration. The detection leverages PowerShell operational logs to identify instances where this command is executed. Monitoring this activity is crucial as it may indicate an adversary's attempt to gather information about domain users, which is a common step in Active Directory Discovery. If confirmed malicious, this activity could lead to further reconnaissance and potential exploitation of domain resources.

Known false positives

  • Administrators or power users may use this command for troubleshooting.

MITRE ATT&CK coverage

Telemetry coverage

Rule body

name: Get DomainUser with PowerShell Script Block
id: 61994268-04f4-11ec-865c-acde48001122
version: 13
creation_date: '2021-08-25'
modification_date: '2026-05-13'
author: Teoderick Contreras, Mauricio Velazco, Splunk
status: production
type: TTP
description: The following analytic detects the execution of the `Get-DomainUser` cmdlet using PowerShell Script Block Logging (EventCode=4104). This cmdlet is part of PowerView, a tool often used for domain enumeration. The detection leverages PowerShell operational logs to identify instances where this command is executed. Monitoring this activity is crucial as it may indicate an adversary's attempt to gather information about domain users, which is a common step in Active Directory Discovery. If confirmed malicious, this activity could lead to further reconnaissance and potential exploitation of domain resources.
data_source:
    - Powershell Script Block Logging 4104
search: |-
    `powershell` EventCode=4104 ScriptBlockText = "*Get-DomainUser*"
      | 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_domainuser_with_powershell_script_block_filter`
how_to_implement: The following Hunting analytic requires PowerShell operational logs to be imported. Modify the powershell macro as needed to match the sourcetype or add index. This analytic is specific to 4104, or PowerShell Script Block Logging.
known_false_positives: Administrators or power users may use this command for troubleshooting.
references:
    - https://powersploit.readthedocs.io/en/latest/Recon/Get-DomainUser/
finding:
    title: Powershell process having commandline "*Get-DomainUser*" for user enumeration on $dest$
    entity:
        field: user_id
        type: user
        score: 50
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 50
          message: Powershell process having commandline "*Get-DomainUser*" for user enumeration on $dest$
analytic_story:
    - Active Directory Discovery
    - CISA AA23-347A
asset_type: Endpoint
mitre_attack_id:
    - T1087.002
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint

Stages and Predicates

Stage 1: search

`powershell` EventCode=4104 ScriptBlockText = "*Get-DomainUser*"

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_domainuser_with_powershell_script_block_filter`

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
EventCodeeq
  • 4104 corpus 269 (splunk 269)
field:"EventID" kind:eq value:"4104"
ScriptBlockTexteq
  • "*Get-DomainUser*" corpus 3 (splunk 3)
field:"ScriptBlockText" kind:eq