Detection rules › Splunk

GetWmiObject DS User with PowerShell

Status
production
Severity
low
Group by
IntegrityLevel, command_line, computer_name, event_action, original_file_name, parent_command_line, parent_process_guid, parent_process_id, parent_process_name, process_guid, process_hash, process_id, process_name, user, user_id, vendor_product
Author
Teoderick Contreras, Mauricio Velazco, Splunk
Source
github.com/splunk/security_content

The following analytic detects the execution of powershell.exe with command-line arguments used to query domain users via the Get-WmiObject cmdlet and -class ds_user parameter. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant as it indicates potential reconnaissance efforts by adversaries to enumerate domain users, which is a common step in Active Directory Discovery. If confirmed malicious, this could lead to further attacks, including privilege escalation and lateral movement within the network.

MITRE ATT&CK coverage

Event coverage

Rule body splunk

name: GetWmiObject DS User with PowerShell
id: 22d3b118-04df-11ec-8fa3-acde48001122
version: 11
creation_date: '2021-08-25'
modification_date: '2026-05-13'
author: Teoderick Contreras, Mauricio Velazco, Splunk
status: production
type: Anomaly
description: |-
    The following analytic detects the execution of `powershell.exe` with command-line arguments used to query domain users via the `Get-WmiObject` cmdlet and `-class ds_user` parameter.
    This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions.
    This activity is significant as it indicates potential reconnaissance efforts by adversaries to enumerate domain users, which is a common step in Active Directory Discovery.
    If confirmed malicious, this could lead to further attacks, including privilege escalation and lateral movement within the network.
data_source:
    - Sysmon EventID 1
    - Windows Event Log Security 4688
    - CrowdStrike ProcessRollup2
search: |-
    | tstats `security_content_summariesonly`
      count min(_time) as firstTime
            max(_time) as lastTime
    
    from datamodel=Endpoint.Processes where
    
    (
        `process_powershell`
        OR
        `process_cmd`
    )
    AND
    Processes.process = "*get-wmiobject*"
    Processes.process = "*ds_user*"
    Processes.process = "*root\\directory\\ldap*"
    Processes.process = "*-namespace*"
    
    by Processes.action Processes.dest Processes.original_file_name
       Processes.parent_process Processes.parent_process_exec
       Processes.parent_process_guid Processes.parent_process_id
       Processes.parent_process_name Processes.parent_process_path
       Processes.process Processes.process_exec Processes.process_guid
       Processes.process_hash Processes.process_id
       Processes.process_integrity_level Processes.process_name
       Processes.process_path Processes.user
       Processes.user_id Processes.vendor_product
    
    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `getwmiobject_ds_user_with_powershell_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: |-
    Administrators or power users may use this command for troubleshooting.
references:
    - https://jpcertcc.github.io/ToolAnalysisResultSheet/details/dsquery.htm
drilldown_searches:
    - name: View the detection results for - "$user$" and "$dest$"
      search: '%original_detection_search% | search  user = "$user$" dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$" and "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
intermediate_findings:
    entities:
        - field: user
          type: user
          score: 20
          message: an instance of process $process_name$ with commandline $process$ on $dest$
        - field: dest
          type: system
          score: 20
          message: an instance of process $process_name$ with commandline $process$ on $dest$
threat_objects:
    - field: parent_process_name
      type: parent_process_name
analytic_story:
    - Active Directory Discovery
asset_type: Endpoint
mitre_attack_id:
    - T1087.002
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/T1087.002/AD_discovery/windows-sysmon.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

Stages and Predicates

Stage 1: tstats

| tstats `security_content_summariesonly`
  count min(_time) as firstTime
        max(_time) as lastTime

from datamodel=Endpoint.Processes where

(
    `process_powershell`
    OR
    `process_cmd`
)
AND
Processes.process = "*get-wmiobject*"
Processes.process = "*ds_user*"
Processes.process = "*root\\directory\\ldap*"
Processes.process = "*-namespace*"

by Processes.action Processes.dest Processes.original_file_name
   Processes.parent_process Processes.parent_process_exec
   Processes.parent_process_guid Processes.parent_process_id
   Processes.parent_process_name Processes.parent_process_path
   Processes.process Processes.process_exec Processes.process_guid
   Processes.process_hash Processes.process_id
   Processes.process_integrity_level Processes.process_name
   Processes.process_path Processes.user
   Processes.user_id Processes.vendor_product

Stage 2: search

| `drop_dm_object_name(Processes)`

Stage 3: search

| `security_content_ctime(firstTime)`

Stage 4: search

| `security_content_ctime(lastTime)`

Stage 5: search

| `getwmiobject_ds_user_with_powershell_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
Processes.original_file_nameeq
  • "Cmd.Exe" corpus 65 (sigma 43, splunk 17, elastic 5)
  • "PowerShell.EXE" corpus 120 (sigma 84, splunk 30, elastic 6)
  • "powershell_ise.EXE" corpus 51 (splunk 30, sigma 18, elastic 3)
  • "pwsh.dll" corpus 112 (sigma 79, splunk 30, elastic 3)
Processes.processeq
  • "*-namespace*"
  • "*ds_user*" corpus 2 (splunk 2)
  • "*get-wmiobject*" corpus 6 (splunk 5, sigma 1)
  • "*root\\directory\\ldap*" corpus 2 (splunk 2)
Processes.process_nameeq
  • "cmd.exe" corpus 77 (elastic 48, splunk 29)
  • "powershell.exe" corpus 104 (elastic 60, splunk 44)
  • "powershell_ise.exe" corpus 50 (splunk 29, elastic 21)
  • "pwsh.exe" corpus 62 (elastic 33, splunk 29)