Question

My website was recently attacked by, what seemed to me as, an innocent code:

<?php   if ( isset( $ _GET['page'] ) ) {     include( $ _GET['page'] . '.php' );   } else {     include('home.php');   } ?> 

There where no SQL calls, so I wasn’t afraid for SQL Injection. But, apparently, SQL isn’t the only kind of injection.

This website has an explanation and a few examples of avoiding code injection: http://www.theserverpages.com/articles/webmasters/php/security/Code_Injection_Vulnerabilities_Explained.html

How would you protect this code from code injection?

Answer 1

Use a whitelist and make sure the page is in the whitelist:

  $whitelist = array('home', 'page');    if (in_array($_GET['page'], $whitelist)) {         include($_GET['page'].'.php');   } else {         include('home.php');   }