MyBB Bans List 1.0 - Cross-Site Scripting

# Exploit Title: MyBB Bans List - Cross Site Scripting
# Date: 7/25/2018
# Author: 0xB9
# Twitter: @0xB9Sec
# Contact: 0xB9[at]pm.me
# Software Link: https://community.mybb.com/mods.php?action=view&pid=423
# Version: 1.0
# Tested on: Ubuntu 18.04
# CVE: CVE-2018-14724


1. Description:
Adds bans.php page, showing a list of banned users and the reason of ban. 

Any forum user that's a mod can ban users and input a payload into the ban reason which gets executed on the bans.php page.
 

2. Proof of Concept:

- Have a mod account
- Ban a user
- Input the following for reason of the ban   <script>alert('XSS')</script>
- Anyone to view page will execute payload