"security""javascript""nodejs"
6 min readPrototype Pollution: The JavaScript Vulnerability That Hides in Plain Sight 🧬☠️
Your npm package does a harmless-looking deep merge. An attacker sends one crafted JSON payload. Suddenly every object in your Node.js app has extra properties you never added — and your authentication logic starts returning true for everyone. Welcome to Prototype Pollution.
Mar 04, 2026