One of the most common ways your WordPress blog can be compromised would be by brute force attacks. A brute force attack is the most widely known password cracking method. This attack simply tries to use every possible character combination as a password. To recover a one-character password it is enough to try 26 combinations (‘a’ to ‘z’). Luckily, a WordPress plugin is there to protect your blog from such attacks.
Login LockDown records the IP address and timestamp of every failed WordPress login attempt. If more than a certain number of attempts are detected within a short period of time from the same IP range, then the login function is disabled for all requests from that range. This helps to prevent brute force password discovery.
Currently the plugin defaults to a 1 hour lock out of an IP block after 3 failed login attempts within 5 minutes. This can be modified via the Options panel. Admisitrators can release locked out IP ranges manually from the panel.
1. Extract loginlockdown-1.2.zip into your wp-content/plugins directory into its own folder (note: not the root plugins folder, as this may cause the activation routine to fail).
2. Activate the plugin in the Plugin options.
3. Customize the settings from the Options panel, if desired.
Requires at least WordPress 2.5, tested up to 2.5.1, however, I’m using it on my WordPress 2.7 blog with no problems at all.
Dowmload Login Lockdown here.