Detection: Powershell Execute COM Object

Updated Date: 2025-02-10 ID: 65711630-f9bf-11eb-8d72-acde48001122 Author: Teoderick Contreras, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects the execution of a COM CLSID through PowerShell. It leverages EventCode 4104 and searches for specific script block text indicating the creation of a COM object. This activity is significant as it is commonly used by adversaries and malware, such as the Conti ransomware, to execute commands, potentially for privilege escalation or bypassing User Account Control (UAC). If confirmed malicious, this technique could allow attackers to gain elevated privileges or persist within the environment, posing a significant security risk.

1`powershell` EventCode=4104 ScriptBlockText = "*CreateInstance([type]::GetTypeFromCLSID*" 
2| fillnull 
3| 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 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `powershell_execute_com_object_filter`

Data Source

Name Platform Sourcetype Source
Powershell Script Block Logging 4104 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-PowerShell/Operational'

Macros Used

Name Value
powershell (source=WinEventLog:Microsoft-Windows-PowerShell/Operational OR source="XmlWinEventLog:Microsoft-Windows-PowerShell/Operational" OR source=WinEventLog:PowerShellCore/Operational OR source="XmlWinEventLog:PowerShellCore/Operational")
powershell_execute_com_object_filter search *
powershell_execute_com_object_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic
T1059.001 PowerShell Execution
T1546.015 Component Object Model Hijacking Persistence
Exploitation
Installation
DE.CM
CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting Value
Disabled true
Cron Schedule 0 * * * *
Earliest Time -70m@m
Latest Time -10m@m
Schedule Window auto
Creates Notable Yes
Rule Title %name%
Rule Description %description%
Notable Event Fields user, dest
Creates Risk Event True
This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.

Known False Positives

network operrator may use this command.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

A suspicious powershell script contains COM CLSID command on host $dest$

Risk Object Risk Object Type Risk Score Threat Objects
dest system 5 No Threat Objects

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation ✅ Passing N/A N/A N/A
Unit ✅ Passing Dataset XmlWinEventLog:Microsoft-Windows-PowerShell/Operational XmlWinEventLog
Integration ✅ Passing Dataset XmlWinEventLog:Microsoft-Windows-PowerShell/Operational XmlWinEventLog

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 7