iThemes Security - Security plugin that provides over 30+ ways to secure and protect your WordPress site.
NinjaFirewall (WP Edition) - A true Web Application Firewall to secure and protect WordPress.
Wordfence - Comprehensive security plugin for WordPress.
Hide My WP Ghost - Hide My WP Ghost is a WordPress Security plugin. Changes and hides WordPress common paths for the Best WP Security against hacker’s bots. The plugin works like security through obscurity solution for a WP website.
Acunetix - Audit your website security and web applications for SQL injection, Cross site scripting and other...
Sucuri - Website Protection, Malware Removal, and Blacklist Prevention