A wordpress security system plugin which will check every HTTP request against a given set of rules to filter out malicious requests.
WordPress Security Plugin - Perform over 23 Basic Security Activities for your blog and get a free malware scan at the same time! See more details at
WordPress core security class: A Web Application Firewall to protect your WordPress web portal
SmartFilter Security is the best security plugin to protect your WordPress site from malicious code injections in your posts and comments.