Even a VPN Won’t Protect You From This Browser Security Vulnerability.

A VPN hides your IP address by rerouting your internet traffic through a remote server, preventing internet snoopers from tracking your online activity. This theoretically means no one, not even your internet service provider, will be able to identify you when you connect to the internet and browse the web.

However, in practice, there are numerous vulnerabilities hackers can exploit. Lifehacker recently reported on a browser fingerprinting method that uses hundreds of data points, such as your hardware specifications, operating system version, web browser, and GPU signature, to create a shadow profile that tracks you even when a VPN is enabled. Another way to intercept your data is by exploiting communication leaks directly within your browser.

Major browsers like Chrome, Firefox, and Edge have a WebRTC feature that allows them to bypass the encrypted TCP tunnel created by your VPN to establish high-speed connections for resource-intensive tasks like video streaming, voice calls, and screen sharing. However, your real IP address remains exposed throughout the entire transmission, giving attackers ample time to intercept the identifying information you’re trying to hide.

Fortunately, VPN providers improve WebRTC leak protection with additional security features, but these protections often require manual configuration in the VPN settings or, if your VPN doesn’t support WebRTC leak protection, directly in your web browser. I’ll show you how to do this step by step to avoid unintentional IP address leaks.

How WebRTC Leaks Bypass Your VPN

WebRTC stands for Web Real-Time Communication, a technology that allows your browser to find the shortest route to connect to another device for high-speed data transfer. It establishes a direct peer-to-peer connection with another device using your public IP address, improving data transfer speeds during video and voice calls, live streaming, and screen sharing.

Surely every internet user has encountered WebRTC connections at least once—for example, during a video call via Google Meet. Since this technology requires your public IP address to establish a faster connection, it bypasses the standard TCP VPN encryption tunnel by using a separate communication protocol called User Datagram Protocol (UDP), which sacrifices security for speed.

WebRTC support is built into most modern web browsers, including Chrome and other Chromium-based browsers, Firefox, Edge, Opera, and even Safari. It’s also enabled by default, meaning your VPN won’t hide your IP address during a video conference or live stream unless you take specific steps to prevent unencrypted data transmission.

How to check for a WebRTC leak

You can check for WebRTC leaks using dedicated online tools that run security checks in your browser while your VPN is enabled. Here’s how:

1. Enable VPN using your provider’s app or browser extension.

2. To check for leaks, open sites like BrowserLeaks or IPLeaks in your browser.

3. See the results in the “WebRTC Leak Test” section of the test report. Note the result corresponding to the “Public IP Address” field.

4. If it says “No IP address leak,” everything is fine. But if it says something like “WebRTC IP address does not match your remote IP address” or your real IP address is displayed anywhere in this section, then you’re vulnerable.

How to disable WebRTC in your browser to prevent IP address leaks.

Many leading VPN providers offer built-in WebRTC protection using network firewalls and kill switches to prevent IP address leaks. However, if a leak test reveals your connection is vulnerable, the safest option is to disable WebRTC connections at the browser level (Chrome, Edge, Firefox, Opera, etc.).

There’s a tradeoff here, as many platforms, including Google Meet and Discord web, require WebRTC functionality to function properly. Therefore, it’s best to disable this feature when viewing sensitive information and re-enable it during a secure video call with someone you know.

Not all browsers handle WebRTC the same way. For example, Firefox allows you to completely disable the feature, while Safari imposes special restrictions to prevent excessive data leakage, and Chrome doesn’t offer a built-in toggle without a third-party plugin. Here’s how to disable WebRTC in most popular web browsers:

Disabling WebRTC in Firefox

Firefox is the only major browser that allows you to completely disable WebRTC without any extensions.

1. Enter about:config in the address bar and accept the risk warning.

2. Find the media.peerconnection.enabled parameter.

3. Double-click the entry to change its value from true to false.

Please note that this will break any website that relies on WebRTC functionality, including video calls on Google Meet or Discord.

Disabling WebRTC in Chrome

Chrome doesn’t have a built-in WebRTC toggle feature, so you’ll need a browser extension specifically designed to control WebRTC handling, such as the WebRTC Control extension available in the Chrome Web Store.

1. Install a reliable WebRTC control extension from the Chrome Web Store.

2. Set the WebRTC IP address handling option to “Disable UDP without proxying”.

3. Refresh the leak test page to ensure your real IP address is no longer displayed.

Be selective about which extensions you install—a tool designed to restrict WebRTC usage has no legal basis for requesting access to your browsing history or the content of every page you visit.

Disabling WebRTC in Edge

Edge runs on the same Chromium engine as Chrome, so the solution is the same: there’s no built-in disable button, but you can use a browser extension from the Microsoft Edge add-on store or the Chrome Web Store to disable WebRTC.

1. Install a WebRTC blocking extension compatible with Edge.

2. Configure it to disable UDP without proxying or block WebRTC completely, depending on what it supports.

3. If you’re happy to keep WebRTC enabled while hiding your IP address, you can enter edge://flags into your browser’s address bar and enable the “Anonymize local IP addresses provided by WebRTC” option without installing the extension.

4. Please retest with your VPN connected to ensure the leak is fixed.

Should You Really Worry About WebRTC Leaks?

It seems like a new security vulnerability makes headlines almost every day, so you might be wondering if all these precautions are worth it.

If you want to follow my rule of thumb, I’d say that if you care enough about privacy to use a VPN, you should also pay attention to WebRTC handling in your browser and, at a minimum, anonymize your IP address for UDP connections, and, in extreme cases, disable WebRTC entirely. Keep in mind that WebRTC remains enabled by default even when your browser is in incognito mode and you’re simultaneously using a VPN, so the extra precautions are worth it if you care about additional privacy.

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