Here it is, AdminCP Firewall for xenForo!
The vBulletin version of this add-on has, at the time of writing, surpassed 41 installs and 150 downloads - and is in the running to win April 2014's MOTM!
This add-on is a hackers nightmare - and an admin's dream. It provides a suite of tools to protect your AdminCP from attack.
Here's the feature list:
Allow access to AdminCP based on IP.
E-Mail when someone logs in with an invalid IP.
E-Mail when someone logs in to the AdminCP.
E-Mail when someone fails an AdminCP login.
With all those features enabled (and yes, they can be disabled individually), your AdminCP will be as secure as it can be!
Sorry, but you need at least 25 posts and 5 hours online time to unlock hidden content.