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

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-04
Updated
2026-09-04

ATT&CK techniques

Persistence
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects a Chromium-based browser launched with --load-extension pointing at an extension in AppData, Temp or ProgramData, the persistence behavior ChromeLoader uses to inject a malicious browser extension. Loading an unpacked extension from a user-writable path is a technique tracked in the Red Canary Threat Detection Report. Detecting this invocation surfaces browser hijacking for adware or credential theft.

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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 Extension Sideload From a User Path (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.