WebRTC & Public IP Leak Diagnostic Test

Understanding the WebRTC IP Leak Vulnerability

WebRTC (Web Real-Time Communication) is an open-source framework supported by Apple, Google, Microsoft, and Mozilla. It allows modern web browsers to transmit real-time video, audio, and peer-to-peer data directly without external plugins.

To establish this direct peer connection between two devices behind NAT (Network Address Translation) routers, WebRTC uses the STUN (Session Traversal Utilities for NAT) protocol. During this process, your browser broadcasts its local internal IP address (e.g. 192.168.1.x) and its external public gateway IP.

Why VPNs Fail Against WebRTC Leaks

Many consumer-grade VPN applications only tunnel standard TCP and UDP socket traffic initiated by operating system applications. However, modern browsers execute STUN requests at a lower socket level that can bypass the VPN virtual adapter tunnel, silently sending STUN packets through your default ISP gateway.

Consequently, any malicious website or tracking script can execute simple JavaScript API calls (RTCPeerConnection) to reveal your true geographic location and ISP identity, rendering your VPN ineffective.

How to Protect Against WebRTC Leaks

• Enable Browser Extension WebRTC Blocking: Use trusted privacy extensions or browser flags to disable non-proxied UDP bindings.
• Use an Audited VPN with Native Leak Protection: Top tier VPN services like Surfshark, NordVPN, and Proton automatically inject packet filtering rules that disable WebRTC leaks system-wide.