Wordpress Plugin UserPro < 4.9.21 - User Registration Privilege Escalation 2019-01-07 18:05:04

# Exploit Title: Wordpress Plugin UserPro < 4.9.21 User Registration With Administrator Role
# Google Dork: inurl:/wp-content/plugins/userpro/
# Date: 3rd January, 2019
# Exploit Author: Noman Riffat
# Vendor Homepage: https://userproplugin.com/
# Software Link: https://codecanyon.net/item/userpro-user-profiles-with-social-login/5958681
# Version: < 4.9.21
# Tested on: Wordpress 4.9.9 with linux but should work on all WP versions and OS as well

UserPro fixed a user registration with administrator privileges vulnerability in version 4.9.21
But there wasn't any POC available so this exploit demonstrates this
From the changelog: "Security Fix : Registration role validation fix"

The latest version up to now is 4.9.29
The vulnerability allows anyone to register with Administrator role which
can easily be turned into RCE

Steps to reproduce:

1. Go to the registration form, input random fake values, trigger Burp
Suite and click submit.

2. The POST data will look similar to following

[email protected]

Here "-701" is a random postfix number and gets stripped at the server.
Other than that, the interesting values are


3. Adding following extra parameter in POST data will register the user
with Administrator privileges


So the modified POST data will look similar to following


4. Forward the POST data in Burp Suite and you will get redirect to
/profile/ page with Administrator menu on top. Access /wp-admin/ to get to
the dashboard

5. Upload shell with default methods