WordPress plugin: Protect your blog from malicious URL Requests

Due to its popularity, WordPress is often the target of hackers. Today, let’s see how we can build a plugin that will check for malicious URL requests (Long request strings, presence of either “eval” and “base64″ php functions, etc.) and use it to protect our blog.

Paste the following code into a text file, and save it as blockbadqueries.php

<?php 
 /*  Plugin Name: Block Bad Queries
  Plugin URI: http://h20bikash.blogspot.com/
  Description: Protect WordPress Against Malicious URL Requests  
Author URI: http://h20bikash.blogspot.com  
Author: Jibon Bikash Roy  Version: 1.0  
*/  
global $user_ID; if($user_ID)
 {  
  if(!current_user_can('level_10'))
 {  
    if (strlen($_SERVER['REQUEST_URI']) > 255 || strpos($_SERVER['REQUEST_URI'], "eval(") || strpos($_SERVER['REQUEST_URI'], "CONCAT") || strpos($_SERVER['REQUEST_URI'], "UNION+SELECT") || strpos($_SERVER['REQUEST_URI'], "base64")) 
{   
       @header("HTTP/1.1 414 Request-URI Too Long");
   @header("Status: 414 Request-URI Too Long");
   @header("Connection: Close"); 
  @exit; 
     } 
   } 
 }


?>