Programming & Scripting for Pentesters
JavaScript & TypeScript for Web Attacks
The language of the web is the language of web exploitation.
Every web app runs JavaScript. To exploit the web deeply — XSS payloads, DOM analysis, Node.js internals, prototype pollution — you must read and write JS/TS fluently.
- XSS payload crafting — DOM APIs, event handlers, encoding tricks.
- Reading front-end bundles — hunt for API keys, hidden endpoints, and logic in JS files.
- Node.js internals — server-side JS bugs (prototype pollution, command injection via child_process, SSRF).
- Automation — Playwright/Puppeteer to script authenticated flows and DOM XSS testing.
// Pull all endpoints out of a front-end bundle
[...document.scripts].map(s => s.src);
// Then fetch and regex for '/api/...' paths, tokens, and secrets.