Suspicious Browser Launch with Unpacked Extension Loaded via load-extension (via process_creation)

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1176Software Extensions
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects chrome.exe or msedge.exe launched with the --load-extension argument, the browser-hijacking persistence Red Canary observed for sideloading an unpacked extension without user interaction. Adversaries use this flag to inject a malicious extension for credential and session theft, so its use outside developer workflows warrants review.

Reporting behind it

Related detections9 linkedT1176 — drag to rearrange

Malicious GenAI Browser Extension C2 and PAC Redirection (via proxy)

Suspicious Microsoft Edge Headless Launch with Unpacked Extension via SNOWBELT (via process_creation)

Suspicious Browser Extension Force-Install via Registry (via registry_set)

Suspicious Microsoft Edge Native Messaging Host Registration via UNC6692

Malicious Madgicx Plus Chrome Extension Identifiers on Disk

Suspicious Browser Extension Sideload From a User Path (via process_creation)

Suspicious Chrome Remote Debugging Port for Browser Session Theft

Suspicious Microsoft Edge Unpacked Extension Load via UNC6692 Edgecution

Malicious Chrome Extension Sideload via --load-extension from User-Writable Path (via process_creation)

Suspicious Browser Launch with Unpacked Extension Loaded via load-extension (via process_creation)

Pivot detection · T1176 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →