What Is a WebRTC Leak? How to Detect and Stop It

A WebRTC leak is a browser-level vulnerability that exposes your real IP address to websites — even when you are connected to a VPN. It is caused by WebRTC (Web Real-Time Communication), a legitimate browser technology used for video calls and peer-to-peer file transfer. The problem is that WebRTC discovers device IP addresses using a process that runs at the browser level, outside the VPN tunnel, making it possible for any website to query your real IP through JavaScript regardless of what your VPN is doing at the network level.

What Is WebRTC and Why Does It Cause IP Leaks?

WebRTC is built into every modern browser to enable direct browser-to-browser communication — the technology behind Google Meet, Discord web, Zoom browser, and peer-to-peer file sharing. To establish connections between users, WebRTC uses a process called ICE (Interactive Connectivity Establishment) that discovers all available network paths. This process queries the device for every IP address it has — including your real ISP-assigned IP — and makes this information accessible to websites through a JavaScript API.

Your VPN masks your IP at the network layer. WebRTC leaks occur at the browser layer — a completely different level. The VPN sees only encrypted packets. The browser WebRTC API sees your actual network interface IPs. When a website uses JavaScript to make a WebRTC STUN request, the browser responds with your real IP, bypassing whatever the VPN is doing to mask your address at the network level.

Which Browsers Are Affected?

Browser	WebRTC Enabled	Built-in Leak Protection	What to Do
Google Chrome	Yes	No	Install extension
Mozilla Firefox	Yes	Partial	Change about:config
Microsoft Edge	Yes	No	Install extension
Apple Safari	Limited	Yes	No action needed
Brave Browser	Yes	Yes (randomized)	No action needed
Opera	Yes	No	Install extension

How to Test for a WebRTC Leak

Connect your VPN, then visit the SitusProxy WebRTC Leak Test. The test uses the same JavaScript API a malicious website would use to query your browser for IP addresses. Compare the IPs shown against your real IP — visible from the IP Checker without any VPN active. If the WebRTC test shows an IP matching your real ISP connection rather than your VPN server IP, you have a confirmed WebRTC leak.

How to Fix WebRTC Leaks

Fix WebRTC Leak in Firefox

Firefox allows direct configuration to disable WebRTC entirely. Type about:config in the Firefox address bar and press Enter. Accept the risk warning. Search for media.peerconnection.enabled. Double-click this preference to change its value from true to false. WebRTC is now completely disabled in Firefox. The only side effect is that browser-based video calls will not work in this profile — installed apps like Zoom and Teams are completely unaffected.

Fix WebRTC Leak in Chrome

Chrome does not provide a built-in toggle for WebRTC. Install the WebRTC Network Limiter extension from the Chrome Web Store — it is maintained by Google and prevents WebRTC from accessing your real IP. Alternatively, NordVPN Chrome extension includes WebRTC leak blocking as a built-in feature alongside full VPN encryption protection.

Switch to Brave Browser

Brave Browser provides the strongest default WebRTC protection of any major browser. It randomizes the local IP addresses reported through WebRTC, so even if a website queries the API, it receives a fake IP rather than your real address. Brave requires no configuration to prevent WebRTC leaks — it is protected by default.

Does a VPN Protect Against WebRTC Leaks?

A VPN alone does not prevent WebRTC leaks. VPNs operate at the network layer; WebRTC leaks occur at the browser layer. These are different levels of the software stack, and network-level encryption cannot block browser-level IP exposure. To be protected against WebRTC leaks while using a VPN, you need a browser extension from your VPN provider that specifically addresses WebRTC, or a browser with built-in WebRTC protection like Brave.

Frequently Asked Questions