vulnerability prototype pollution
severity 4.8
language javascript
registry npm


fine-uploader is a npm package for upload. Note: This project is no longer maintained and the the package should be considered deprecated. Affected versions of this package are vulnerable to Prototype Pollution. Given a value such as proto, this value is used by the extend function without any prior validation. proto will modify the properties of all existing properties and new properties resulting in pollution of an object's prototype.

Proof of Concept

// var payload = JSON.parse('{"proto": {"a": "polluted"}}'); var new = qq.extend({}, payload); console.log({}.a);