Uncommon Browser Launched with Remote Debugging Port for Cookie Theft (via process_creation)

ATT&CK techniques

Cred Access

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1539Steal Web Session Cookie
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a Chromium-based browser started with a remote debugging port flag, the technique Electron-based gaming stealers use to attach to the browser and dump cookies directly from a debugged instance. Adversaries launch the browser in debug mode to bypass cookie encryption and harvest session tokens. Debug-mode browser launches are rare outside developer tooling.

Reporting behind it

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Uncommon Browser Launched with Remote Debugging Port for Cookie Theft (via process_creation)

Pivot detection · T1539 · 9 related

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