What is a WebRTC leak?
A WebRTC leak, like a DNS-leak, is the capability to get your real address even while you are using some anonymization services.
What is the WebRTC technology?
WebRTC (Web Real-Time Communication) is a technology that allows you to organize the flow of data between browsers. It is currently supported by Firefox and Chrome, as well as all browsers that are based on Chrome. The technology basically allows voice and video communication in browsers.
The leak of the IP address (local and external) occurs by calling the command using WebRTC. Typically, this command is called by javascript.
There are two solutions for this problem - prohibiting the execution of all scripts in the browser and/or disabling the WebRTC technology in the browser.