WebRTC is an API with the purpose of enabling a direct link between web browsers when using services like VoIP and file sharing peer-to-peer. WebRTC is included in the majority of web browsers.
It can however also leak your private IP addresses even though you're connnected to a VPN service.
The easiest way to protect yourself is to install our browser extension for Chrome and Firefox. The extension protects you against IP leaks without entirely disabling WebRTC meaning you can still reap the benefits of WebRTC.
Another option would be to install uBlock Origin in case you use a different browser or don't want to install our extension. If you’re using Firefox, you can visit about:config in the browser and search for media.peerconnection.enabled and change the value to False by double clicking on it.
WebRTC sends so-called STUN requests, returning your network adaptor’s internal and external IP addresses. Since these STUN requests are made through UDP, they are not transported over HTTP or SOCKS, which both are based on the networking protocol TCP. This is what a request looks like: