How DOM Invader works

We're not going to go into a full demo of how to use DOM Invader here (please see the documentation for that), but as a broad overview, you're going to be spending a lot of your time using the tool in the Augmented DOM. The Augmented DOM will show you all the sources and sinks contained within your target, and allows you to find DOM XSS as if it were reflected XSS - by inspecting the value sent to the sink.

Essentially, you'll load up the site you want to test, and insert your canary into a query parameter or other such source. Opening DevTools in Burp Suite's embedded browser, you'll be able to click on a new "Augmented DOM" tab - which will show you any sources and sinks containing the canary value - as well as a tree view of all the sources and sinks available. Helpfully, DOM Invader orders sinks so that the most interesting ones appear first.

Read more : Introducing DOM Invader: DOM XSS just got a whole lot easier to find | Blog - PortSwigger 

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