WordPress Plugin Sell Downloads 1.0.86 - Cross-Site Scripting

# Exploit Title: WordPress Plugin Sell Downloads 1.0.86 - Cross Site Scripting
# Exploit Author: Mr Winst0n
# Author E-mail: [email protected]
# Discovery Date: September 09,2019
# Vendor Homepage: https://wordpress.dwbooster.com/content-tools/sell-downloads
# Software Link : https://wordpress.org/plugins/sell-downloads/
# Tested Version: 1.0.86
# Tested on: Parrot OS, Wordpress 5.1.1


# PoC:
1- Go to "Products for Sale" section
2- Click on "Add New"
3- In opend window click on "Add Comment"
4- Fill comment as "/><img src=x onerror="alert()"> or "/><input type="text" onclick="alert()">
5- Click on "Publish" (or "Update" if you editing an existing product)
6- You will see a pop-up (also if click on input), Also if you go to product link will see the pop-up.