Offensive Callback (III): Inside the Browser Stealer — merch.js

Third post in the Offensive Callback series. This is the deep dive into the client-side JavaScript payload — what I call merch.js internally, served as dl.full.min.js by the XSS dealer. It’s the piece that runs in a victim’s browser and does all the actual collection work. The file is about 10,000 lines minified and bundles several libraries: a hashing lib..