My ISP just shut down my Registration script...
 

"We regret to inform you that we needed to disable the following script
located in your account because a security vulnerability within it was
exploited by a malicious user to run commands on the server:

/usr/www/users/p15d24/mopar_forum/register.php"

I don't have any additional info as to what was the specific issue.

Yes, I'm running an older version (v3.6) but did any upgrade version address any security vulnerabilities with this script? I looked through the release notes and searched bugs without any success. Time to upgrade?