With WordPress installations on the rise, security threats are a common concern for users. Below is a small collection of WordPress plugins that I found adequate for use on most WordPress installations to keep security in check. As always security is not 100% achievable, but the following plugins will help you find any loopholes in your site and help you monitor for any security breaches.
BulletProof Security protects your website from XSS, RFI, CSRF, Base64, Code Injection and SQL Injection hacking attempts. The plugin also Protects wp-config.php, bb-config.php, php.ini, php5.ini, install.php and readme.html with .htaccess security protection. BPS has built-in Backup and Restore, a File Editor, a File Uploader and a File Downloader to make managing the BPS master .htaccess files and your website security fast and simple.
WordPress File Monitor
WFM monitors your WordPress installation for any added, deleted or changed files. When a change is detected an email is sent to a specified address. Currently does not support multi-site installations.
Ultimate Security Checker
Ultimate Security Checker helps you identify security problems with your WordPress installation. It scans your WordPress blog for hundreds of known threats, then gives you a security “grade” based on how well you have protected yourself.