Powershell Execute COM Object
Description
This search is to detect a COM CLSID execution through powershell. This technique was seen in several adversaries and malware like ransomware conti where it has a feature to execute command using COM Object. This technique may use by network operator at some cases but a good indicator if some application want to gain privilege escalation or bypass uac.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-03-22
- Author: Teoderick Contreras, Splunk
- ID: 65711630-f9bf-11eb-8d72-acde48001122
Annotations
ATT&CK
Kill Chain Phase
- Exploitation
NIST
CIS20
CVE
Search
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`powershell` EventCode=4104 ScriptBlockText = "*CreateInstance([type]::GetTypeFromCLSID*"
| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer user_id
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `powershell_execute_com_object_filter`
Macros
The SPL above uses the following Macros:
powershell_execute_com_object_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- _time
- ScriptBlockText
- Computer
- EventCode
How To Implement
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
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
5.0 | 10 | 50 | A suspicious powershell script contains COM CLSID command in $ScriptBlockText$ with EventCode $EventCode$ in host $Computer$ |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
Reference
- https://threadreaderapp.com/thread/1423361119926816776.html
- https://www.splunk.com/en_us/blog/security/hunting-for-malicious-powershell-using-script-block-logging.html
Test Dataset
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 | version: 2