I thought I’d put together a quick post with links to various cPanel & WHM plugins. I haven’t used all of these, so don’t consider this an endorsement of any kind. 
For now, check out the cPanel forums apps and plugins area which in you might find better reviews.
Eventually I’ll post a review of these (at least the free ones) as time allows.
Free WHM Plugins
- ConfigServer.com Firewall – manages iptables, handles brute force attacks, and much more. This is one that I’ve used, and definitely recommend.
- ConfigServer.com ModSec Control – modify ModSecurity rules on a global or per-user basis, and view logs.
- NDCHost’s Clean Backups – clean backups for accounts which don’t exist after a certain period, automated, or on a manual basis.
- NDCHost’s Account DNS Check – Checks and reports domains which don’t resolve to the assigned IPs in http.conf.
- ConfigServer.com Explorer – provides a “File Manager-like” interface allowing you access to your filesystem via GUI.
- ConfigServer.com Mail Queues – Stats and management of your server’s mail queue.
- ConfigServer.com Mail Manage – Management of your email accounts, important statistics, and displays of accounts over quota, over a certain size, etc.
Pay WHM Plugins
- ConfigServer.com’s eXploit Scanner – active scanning of your server to prevent exploits.
- NDCHost’s Secondary MX – Turns a cPanel DNSonly install into a backup MX server.
Free cPanel Plugins
- cPanel’s cPAddons – Allows installation of several popular PHP scripts. Installed via WHM >> Install cPAddons.
Pay cPanel Plugins
- Netenberg’s Fantastico – Installs over 50 popular PHP scripts [List]. The vast majority are free, open-source software, though a few require a license.
- Softaculous – over 130 PHP scripts.
