Detection: Windows Service Stop By Deletion

Description

The following analytic detects the use of sc.exe to delete a Windows service. It leverages Endpoint Detection and Response (EDR) data, focusing on process execution logs that capture command-line arguments. This activity is significant because adversaries often delete services to disable security mechanisms or critical system functions, aiding in evasion and persistence. If confirmed malicious, this action could lead to the termination of essential security services, allowing attackers to operate undetected and potentially escalate their privileges or maintain long-term access to the compromised system.

Search

1
2| tstats `security_content_summariesonly` values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name = sc.exe OR Processes.original_file_name = sc.exe) Processes.process="* delete *" by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id 
3| `drop_dm_object_name(Processes)` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `windows_service_stop_by_deletion_filter`

Data Source

Name	Platform	Sourcetype	Source
CrowdStrike ProcessRollup2	N/A	'crowdstrike:events:sensor'	'crowdstrike'
Sysmon EventID 1	Windows	'xmlwineventlog'	'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688	Windows	'xmlwineventlog'	'XmlWinEventLog:Security'

Macros Used

Annotations

Default Configuration

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

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

It is possible administrative scripts may start/stop/delete services. Filter as needed.

Associated Analytic Story

• Azorult

• Graceful Wipe Out Attack

Risk Based Analytics (RBA)

References

• https://app.any.run/tasks/a6f2ffe2-e6e2-4396-ae2e-04ea0143f2d8/

• https://thedfirreport.com/2020/04/20/sqlserver-or-the-miner-in-the-basement/

• https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1543.003/T1543.003.md

Detection Testing

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: 3