Suspicious Chrome Remote Debugging Port for Browser Session Theft

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 a Chromium based browser being started with a remote debugging port enabled, which exposes a local DevTools protocol endpoint an attacker can drive to read cookies and session data. XCSSET v4.0 launches Chrome with CDP on a local port to hijack authenticated browser sessions. Detecting the debugging port surfaces browser session theft staged through the debugging interface.

Reporting behind it

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Suspicious Chrome Remote Debugging Port for Browser Session Theft

Pivot detection · T1176 · 8 related

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

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