WordPress Plugin File Upload 4.3.2 - Stored Cross-Site Scripting

# Exploit Title: WordPress Plugin WordPress File Upload 4.3.2 - Stored XSS
# Date: 31/03/2018
# Exploit Author: ManhNho
# Vendor Homepage: https://www.iptanus.com/
# Software Link: https://downloads.wordpress.org/plugin/wp-file-upload.zip
# Version: 4.3.2
# Tested on: CentOS 6.5
# CVE : CVE-2018-9172
# Category : Webapps

1. Description
===========
WordPress File Upload is a WordPress plugin with more than 20.000 active
installations.
Version 4.3.2 (and possibly previous versions) are affected by a Stored XSS
vulnerability in the admin panel ,related to the "Uploader Instances"
functionality.

2. Proof of Concept
===========

1. Login to admin panel
2. Access to Wordpress File Upload Control Panel. In Uploader Instances
function, choose and edit created Instance
3. In Plugin ID field, inject XSS pattern such as:
<script>alert('ManhNho')</script> and click Update button
4. Access to Pages/Posts contain upload option, we got alert ManhNho

3. References
===========
https://www.iptanus.com/new-version-4-3-3-of-wordpress-file-upload-plugin/
https://wordpress.org/plugins/wp-file-upload/#developers
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-9172