MyBB Plugin Downloads 2.0.3 – Cross-Site Scripting

# Exploit Title: MyBB Downloads Plugin v2.0.3 - Persistent XSS

# Date: 3/28/18

# Author: 0xB9

# Contact: luxorforums.com/User-0xB9 or 0xB9[at]protonmail.com

# Software Link: https://community.mybb.com/mods.php?action=view&pid=854

# Version: 2.0.3

# Tested on: Ubuntu 17.10

1. Description:

It is a plugin which adds a page to download files. If enabled, regular members can add new downloads to the page after admin approval.

2. Proof of Concept:

Persistent XSS

- Go to downloads.php page

- Create a New Download

- Add the following to the title <BODY ONLOAD=alert('XSS')>

- Now when the admin goes to validate your download he will be alerted

3. Solution:

Update to the latest release

Patch: https://github.com/vintagedaddyo/MyBB_Plugin-Downloads/pull/1/commits