ID | Technique | Tactic |
---|---|---|
T1569 | System Services | Execution |
T1569.002 | Service Execution | Execution |
Detection: Malicious Powershell Executed As A Service
Description
The following analytic identifies the execution of malicious PowerShell commands or payloads via the Windows SC.exe utility. It detects this activity by analyzing Windows System logs (EventCode 7045) and filtering for specific PowerShell-related patterns in the ImagePath field. This behavior is significant because it indicates potential abuse of the Windows Service Control Manager to run unauthorized or harmful scripts, which could lead to system compromise. If confirmed malicious, this activity could allow attackers to execute arbitrary code, escalate privileges, or maintain persistence within the environment.
Search
1`wineventlog_system` EventCode=7045
2| eval l_ImagePath=lower(ImagePath)
3| regex l_ImagePath="powershell[.\s]
4|powershell_ise[.\s]
5|pwsh[.\s]
6|psexec[.\s]"
7| regex l_ImagePath="-nop[rofile\s]+
8|-w[indowstyle]*\s+hid[den]*
9|-noe[xit\s]+
10|-enc[odedcommand\s]+"
11| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ImagePath ServiceName StartType ServiceType AccountName UserID dest
12| rename UserID as user
13| `security_content_ctime(firstTime)`
14| `security_content_ctime(lastTime)`
15| `malicious_powershell_executed_as_a_service_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
Windows Event Log System 7045 | Windows | 'xmlwineventlog' |
'XmlWinEventLog:System' |
N/A |
Macros Used
Name | Value |
---|---|
security_content_ctime | convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$) |
malicious_powershell_executed_as_a_service_filter | search * |
malicious_powershell_executed_as_a_service_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
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 |
Implementation
To successfully implement this search, you need to be ingesting Windows System logs with the Service name, Service File Name Service Start type, and Service Type from your endpoints.
Known False Positives
Creating a hidden powershell service is rare and could key off of those instances.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
Identifies the abuse the Windows SC.exe to execute malicious powerShell as a service $ImagePath$ by $user$ on $dest$ | 72 | 90 | 80 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | XmlWinEventLog:System |
XmlWinEventLog |
Integration | ✅ Passing | Dataset | XmlWinEventLog:System |
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: 4