In this course, I will first detailed which WebAssembly Javascript APIs are supported by major browsers. Then, I’ll explains how to use Dharma to generate valid Javascript file to fuzz WebAssembly APIs. Finally, I’ll show you an easy way to execute those generated testcases over ASAN build of Chrome/V8 engine.

 In this video, I will first explain how to download Chrome ASAN build. Then, I’ll detail what is DOM (Document Object Model) and how it is used by web browsers. I'll use the FreeDom grammar-based fuzzer to generate some HTML files and create a simple script to process all those files inside chrome. Finally, I’ll show you a tip to speed up your fuzzing.

In this short hands-on workshop, we will attack the V8 JavaScript Engine using grammar-based fuzzing. First, I will show how to download a version of V8 already compiled with addressSanitizer (ASAN). Then, I will introduce how to write a Dharma grammar and finally, we will use some simple scripts to start automation. Most of what you will learn during this workshop can be applied in other JavaScript engines like SpiderMonkey, JavaScriptCore, etc.