What is prototype pollution in Node.js and how can it affect application security?

Question

Node.js Developer — Hard

What is prototype pollution in Node.js and how can it affect application security?

Accepted Answer

Prototype pollution in Node.js is an attack where an adversary modifies Object.prototype, potentially leading to RCE or privilege escalation. This occurs through injecting properties using unsafe object merging or deep clone operations with user-controlled keys like __proto__.