Windows Process Injection With Public Source Path

Name:Windows Process Injection With Public Source Path
id:492f09cf-5d60-4d87-99dd-0bc325532dda
version:8
date:2025-04-16
author:Teoderick Contreras, Splunk
status:production
type:Hunting
Description:The following analytic detects a process from a non-standard file path on Windows attempting to create a remote thread in another process. This is identified using Sysmon EventCode 8, focusing on processes not originating from typical system directories. This behavior is significant as it often indicates process injection, a technique used by adversaries to evade detection or escalate privileges. If confirmed malicious, this activity could allow an attacker to execute arbitrary code within another process, potentially leading to unauthorized actions and further compromise of the system.
Data_source:

• -Sysmon EventID 8

search:`sysmon` EventCode=8 TargetImage = "*.exe" AND NOT(SourceImage IN("C:\\Windows\\*", "C:\\Program File*", "%systemroot%\\*"))
| stats count min(_time) as firstTime max(_time) as lastTime by EventID Guid NewThreadId ProcessID SecurityID SourceImage SourceProcessGuid SourceProcessId StartAddress StartFunction StartModule TargetImage TargetProcessGuid TargetProcessId UserID dest parent_process_exec parent_process_guid parent_process_id parent_process_name parent_process_path process_exec process_guid process_id process_name process_path signature signature_id user_id vendor_product
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_process_injection_with_public_source_path_filter`

how_to_implement:To successfully implement this search, you must be ingesting data that records process activity from your hosts to populate the endpoint data model in the processes node. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.
known_false_positives:Some security products or third party applications may utilize CreateRemoteThread, filter as needed.
References:
  -https://unit42.paloaltonetworks.com/brute-ratel-c4-tool/
drilldown_searches:
  :
tags:
  analytic_story:
    - 'Brute Ratel C4'
    - 'Earth Alux'
  asset_type:Endpoint
  mitre_attack_id:
    - 'T1055.002'
  product:
    - 'Splunk Enterprise'
    - 'Splunk Enterprise Security'
    - 'Splunk Cloud'
  security_domain:endpoint

tests:
 name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/brute_ratel/create_remote_thread/sysmon.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None