Detection rules › Splunk

GetWmiObject DS User 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-WmiObject cmdlet with the DS_User class parameter via PowerShell Script Block Logging (EventCode=4104). It leverages logs to identify attempts to query all domain users using WMI. This activity is significant as it may indicate an adversary or Red Team operation attempting to enumerate domain users for situational awareness and Active Directory discovery. If confirmed malicious, this behavior could lead to further reconnaissance, enabling attackers to map out the network and identify potential targets for privilege escalation or lateral movement.

MITRE ATT&CK coverage

Event coverage

Rule body splunk

name: GetWmiObject DS User with PowerShell Script Block
id: fabd364e-04f3-11ec-b34b-acde48001122
version: 12
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-WmiObject` cmdlet with the `DS_User` class parameter via PowerShell Script Block Logging (EventCode=4104). It leverages logs to identify attempts to query all domain users using WMI. This activity is significant as it may indicate an adversary or Red Team operation attempting to enumerate domain users for situational awareness and Active Directory discovery. If confirmed malicious, this behavior could lead to further reconnaissance, enabling attackers to map out the network and identify potential targets for privilege escalation or lateral movement.
data_source:
    - Powershell Script Block Logging 4104
search: '`powershell` EventCode=4104 ScriptBlockText = "*get-wmiobject*" ScriptBlockText = "*ds_user*" ScriptBlockText = "*-namespace*" ScriptBlockText = "*root\\directory\\ldap*" | 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)` | `getwmiobject_ds_user_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://www.blackhillsinfosec.com/red-blue-purple/
    - https://docs.microsoft.com/en-us/windows/win32/wmisdk/describing-the-ldap-namespace
drilldown_searches:
    - name: View the detection results for - "$dest$" and "$user_id$"
      search: '%original_detection_search% | search  dest = "$dest$" user_id = "$user_id$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$" and "$user_id$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user_id$") | 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"
finding:
    title: powershell process having commandline for user enumeration detected on host - $dest$
    entity:
        field: user_id
        type: user
        score: 50
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 50
          message: powershell process having commandline for user enumeration detected on host - $dest$
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/T1059.001/powershell_script_block_logging/sbl_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*" ScriptBlockText = "*ds_user*" ScriptBlockText = "*-namespace*" ScriptBlockText = "*root\\directory\\ldap*"

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

| `getwmiobject_ds_user_with_powershell_script_block_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
  • "*-namespace*" corpus 2 (sigma 1, splunk 1)
  • "*ds_user*"
  • "*get-wmiobject*" corpus 7 (splunk 5, sigma 2)
  • "*root\\directory\\ldap*"