Try in Splunk Security Cloud

Description

This search is to detect a suspicious excessive usage of sc.exe in a host machine. This technique was seen in several ransomware , xmrig and other malware to create, modify, delete or disable a service may related to security application or to gain privilege escalation.

  • Type: Anomaly
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel: Endpoint
  • Last Updated: 2021-06-24
  • Author: Teoderick Contreras, Splunk
  • ID: cb6b339e-d4c6-11eb-a026-acde48001122

ATT&CK

ID Technique Tactic
T1569 System Services Execution
T1569.002 Service Execution Execution
`sysmon` EventCode = 1 process_name = "sc.exe" 
|  bucket _time span=15m 
| stats values(process) as process count as numScExe by Computer, _time 
|  eventstats avg(numScExe) as avgScExe, stdev(numScExe) as stdScExe, count as numSlots by Computer 
|  eval upperThreshold=(avgScExe + stdScExe *3) 
|  eval isOutlier=if(avgScExe > 5 and avgScExe >= upperThreshold, 1, 0) 
|  search isOutlier=1 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `excessive_usage_of_sc_service_utility_filter`

Associated Analytic Story

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. Tune and filter known instances where renamed taskkill.exe may be used.

Required field

  • _time
  • EventCode
  • process_name
  • process

Kill Chain Phase

  • Exploitation

Known False Positives

excessive execution of sc.exe is quite suspicious since it can modify or execute app in high privilege permission.

Reference

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: 1