Windows Chromium Process Loaded Extension via Command-Line

Name:Windows Chromium Process Loaded Extension via Command-Line
id:1b8a468a-52e3-4206-b14a-73165441684c
version:2
date:2026-01-29
author:Teoderick Contreras, Splunk
status:production
type:Anomaly
Description:The following analytic detects instances where Google Chrome is started with the --load-extension command-line flag, which allows loading unpacked or non-standard extensions. This behavior can indicate attempts to bypass enterprise extension policies, install malicious extensions, or load potentially harmful browser components. Monitoring such activity helps identify unauthorized extension usage, potential malware persistence mechanisms, or policy violations that could compromise browser security.
Data_source:

• -Sysmon EventID 1
• -Windows Event Log Security 4688
• -CrowdStrike ProcessRollup2

search:| tstats `security_content_summariesonly` min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where
Processes.process_name = "Chrome.exe"
Processes.process= "*--load-extension*"

by Processes.action Processes.dest Processes.original_file_name Processes.parent_process
Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id
Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec
Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_chromium_process_loaded_extension_via_command_line_filter`


how_to_implement:To successfully implement this search you need to be ingesting information on process that include the name of the process responsible for the changes from your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.
known_false_positives:Developers or IT admins loading unpacked extensions for testing or deployment purposes.
References:
  -https://www.gdatasoftware.com/blog/2025/11/38298-learning-about-browser-hijacking
  -https://peter.sh/experiments/chromium-command-line-switches/
drilldown_searches:
 name:'View the detection results for - "$user$" and "$dest$"'
 search:'%original_detection_search% | search user = "$user$" dest = "$dest$"'
 earliest_offset:'$info_min_time$'
 latest_offset:'$info_max_time$'
 name:'View risk events for the last 7 days for - "$user$" and "$dest$"'
 search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
 earliest_offset:'$info_min_time$'
 latest_offset:'$info_max_time$'
tags:
  analytic_story:
    - 'Browser Hijacking'
  asset_type:Endpoint
  mitre_attack_id:
    - 'T1185'
  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/attack_techniques/T1185/chrome_load_extensions/chrome_load_extension.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None