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WebRTC Probe ← All Tools
🔒 100% Client-Side In-RAM STUN Audit • Zero Telemetry Logging

WebRTC Leak Test

Verify whether your active VPN or proxy tunnel is leaking your real ISP IP address or local router subnet via WebRTC STUN handshakes.

STUN Handshake Engine Ready
WebRTC Security Status
No WebRTC IP Leaks Detected
Protected

Your browser successfully masked or blocked direct STUN candidate requests. Your true ISP IP is protected from WebRTC extraction.

Public STUN Candidate None Leaked
Local IPv4 Subnet Masked (mDNS)
IPv6 Candidate None Detected
WebRTC API Status Enabled / Sandboxed
Discovered STUN Candidates 0 Candidates

STUN (Session Traversal Utilities for NAT) servers help peers discover direct routes. If your public IP appears above while connected to a VPN, your VPN is leaking.

How to Fix WebRTC Leaks Fix Guide
Firefox Config:

Navigate to about:config and set media.peerconnection.enabled = false.

Brave / Chrome Extensions:

In Brave Shields set WebRTC IP Handling Policy to Disable Non-Proxied UDP or install WebRTC Control.

Cross-Link Diagnostic

Also verify your DNS server anonymity using our Privacy Exposure Scanner.

WebRTC Leak Types: Public IP vs Local mDNS

Understanding the privacy implications of different WebRTC candidate types.

Candidate Type Exposed Data Threat Impact on VPN Users
Server Reflexive (srflx) Public Gateway ISP IP Critical (Bypasses VPN tunnel completely)
Host (host - Raw IP) Internal LAN Subnet (192.168.x.x) Moderate (Leaks internal network topology)
Host (mDNS .local) Randomized UUID (.local) Protected (Standard browser masking)

The Mechanics of WebRTC IP Leaks

Web Real-Time Communication (WebRTC) is an open web standard enabling browsers to exchange peer-to-peer audio, video, and data streams. To establish direct P2P connections through Network Address Translation (NAT) firewalls, browsers query public **STUN (Session Traversal Utilities for NAT)** servers.

1. Why VPNs Frequently Leak WebRTC IP Addresses

Operating system-level VPN clients create encrypted virtual network adapters. However, browser engines can generate UDP STUN packets that bind directly to physical network interfaces (such as Wi-Fi or Ethernet) rather than the virtual VPN adapter, exposing the user's true residential IP address to third-party scripts.

🛡️ Browser Privacy Scanner

Inspect full Canvas, WebGL, and hardware entropy with Privacy Exposure Scanner.

🔗 URL Sharing Risk Checker

Check if links contain secret tokens before sharing with URL Risk Checker.

Frequently Asked Questions

Does this test require sending my IP to UtilyxHub?

No. The WebRTC diagnostic uses public STUN servers (e.g. Google public STUN) strictly to extract candidates in your browser memory (RAM). Zero logs exist on UtilyxHub.

Why does my local IP show as a long uuid.local string?

Modern browsers implement mDNS (Multicast DNS) hostname masking to conceal internal LAN IP addresses (like 192.168.1.5) behind randomized local hashes for privacy protection.

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