Detection: PowerShell Start or Stop Service

Updated Date: 2024-11-13 ID: 04207f8a-e08d-4ee6-be26-1e0c4488b04a Author: Michael Haag, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic identifies the use of PowerShell's Start-Service or Stop-Service cmdlets on an endpoint. It leverages PowerShell Script Block Logging to detect these commands. This activity is significant because attackers can manipulate services to disable or stop critical functions, causing system instability or disrupting business operations. If confirmed malicious, this behavior could allow attackers to disable security services, evade detection, or disrupt essential services, leading to potential system downtime and compromised security.

Search

1`powershell` EventCode=4104 ScriptBlockText IN ("*start-service*", "*stop-service*") 
2| stats count min(_time) as firstTime max(_time) as lastTime by Computer EventCode ScriptBlockText 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `powershell_start_or_stop_service_filter`

Data Source

Name	Platform	Sourcetype	Source
Powershell Script Block Logging 4104	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")`
powershell_start_or_stop_service_filter	`search *`

powershell_start_or_stop_service_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

Installation

DE.AE

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 Risk Event	True

This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup here https://docs.splunk.com/Documentation/UBA/5.0.4.1/GetDataIn/AddPowerShell#Configure_module_logging_for_PowerShell.

Known False Positives

This behavior may be noisy, as these cmdlets are commonly used by system administrators or other legitimate users to manage services. Therefore, it is recommended not to enable this analytic as a direct finding Instead, it should be used as part of a broader set of security controls to detect and investigate potential threats.

Associated Analytic Story

Active Directory Lateral Movement

Risk Based Analytics (RBA)

Risk Message:

PowerShell was identified attempting to start or stop a service on $Computer$.

Risk Object	Risk Object Type	Risk Score	Threat Objects
Computer	system	10	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: 4