Suspicious Connection to Local Zoom Opener Webserver Launch Endpoint (via network_connection)

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1189Drive-by Compromise
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects traffic to the local ZoomOpener helper webserver launch endpoint on loopback port 19421. This maps to the Zoom drive-by RCE chain where a webpage sends a crafted launch request to the hidden local server. An attacker leverages this to trigger silent installation and code execution on the victim host.

Reporting behind it

Related detections6 linkedT1189 — drag to rearrange

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Suspicious Connection to Local Zoom Opener Webserver Launch Endpoint (via network_connection)

Pivot detection · T1189 · 6 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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