Detection rules › Splunk

PowerShell Invoke CIMMethod CIMSession

Status
production
Severity
low
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 creation of a New-CIMSession cmdlet followed by the use of the Invoke-CIMMethod cmdlet within PowerShell. It leverages PowerShell Script Block Logging to identify these specific cmdlets in the ScriptBlockText field. This activity is significant because it mirrors the behavior of the Invoke-WMIMethod cmdlet, often used for remote code execution via NTLMv2 pass-the-hash authentication. If confirmed malicious, this could allow an attacker to execute commands remotely, potentially leading to unauthorized access and control over targeted systems.

Known false positives

  • False positives may be present based on third-party applications or administrators using CIM. It is recommended to apply appropriate filters as needed to minimize the number of false positives.

MITRE ATT&CK coverage

Telemetry coverage

Rule body

name: PowerShell Invoke CIMMethod CIMSession
id: 651ee958-a433-471c-b264-39725b788b83
version: 12
creation_date: '2023-03-22'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: Anomaly
description: The following analytic detects the creation of a New-CIMSession cmdlet followed by the use of the Invoke-CIMMethod cmdlet within PowerShell. It leverages PowerShell Script Block Logging to identify these specific cmdlets in the ScriptBlockText field. This activity is significant because it mirrors the behavior of the Invoke-WMIMethod cmdlet, often used for remote code execution via NTLMv2 pass-the-hash authentication. If confirmed malicious, this could allow an attacker to execute commands remotely, potentially leading to unauthorized access and control over targeted systems.
data_source:
    - Powershell Script Block Logging 4104
search: |-
    `powershell` EventCode=4104 ScriptBlockText IN ("*invoke-CIMMethod*", "*New-CimSession*")
      | 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)`
      | `powershell_invoke_cimmethod_cimsession_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 based on third-party applications or administrators using CIM. It is recommended to apply appropriate filters as needed to minimize the number of false positives.
references:
    - https://learn.microsoft.com/en-us/powershell/module/cimcmdlets/invoke-cimmethod?view=powershell-7.3
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 20
          message: PowerShell was identified running a Invoke-CIMMethod Invoke-CIMSession on $dest$.
analytic_story:
    - Scattered Lapsus$ Hunters
    - Malicious PowerShell
    - Active Directory Lateral Movement
asset_type: Endpoint
mitre_attack_id:
    - T1047
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint

Stages and Predicates

Stage 1: search

`powershell` EventCode=4104 ScriptBlockText IN ("*invoke-CIMMethod*", "*New-CimSession*")

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

| `powershell_invoke_cimmethod_cimsession_filter`

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
EventCodeeq
  • 4104 corpus 269 (splunk 269)
field:"EventID" kind:eq value:"4104"
ScriptBlockTextin
  • "*New-CimSession*"
  • "*invoke-CIMMethod*"
field:"ScriptBlockText" kind:in