Why Browsers Leak IP Addresses Through Proxies
Many users configure a proxy in their browser and believe they are completely anonymous. While an HTTP or SOCKS5 proxy changes the source IP address of standard web requests, certain browser features operate at a lower network tier and can unintentionally leak your true physical IP address.
What is a WebRTC Leak?
WebRTC (Web Real-Time Communication) is an HTML5 technology built into Chrome, Firefox, Safari, and Edge to support seamless browser-to-browser voice calls, video streaming, and P2P data exchange without external plugins. To establish peer connections across firewalls and Network Address Translation (NAT) gateways, WebRTC uses STUN (Session Traversal Utilities for NAT) requests.
Because STUN queries often bypass your browser's configured proxy settings, a malicious website or anti-scraping bot detector can execute JavaScript STUN requests to read your actual public IP address directly from your network interface.
How to Prevent WebRTC Leaks
- Use Dedicated Anti-Detect Browsers: Specialized privacy tools like Dolphin{anty}, AdsPower, or Multilogin completely isolate WebRTC candidates to the proxy IP address. Read our detailed guide on best anti-detect browsers for Connect Proxy.
- Configure Remote DNS in FoxyProxy: When setting up SOCKS5 proxies in Firefox or Chrome extensions, check the option "Send DNS through SOCKS5 proxy". Review our FoxyProxy setup guide for step-by-step instructions.
- Disable WebRTC in Firefox: Type
about:configin your Firefox address bar, search formedia.peerconnection.enabled, and toggle its value to false.