Yorick Koster, July 2016

Cross-Site Scripting in All In One WP Security & Firewall WordPress Plugin

Abstract

A Cross-Site Scripting vulnerability was found in the All In One WP Security & Firewall Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf. In order to exploit this issue, the attacker has to lure/force a logged on WordPress Administrator into opening a malicious website.

Contact

For feedback or questions about this advisory mail us at sumofpwn at securify.nl

The Summer of Pwnage

This issue has been found during the Summer of Pwnage hacker event, running from July 1-29. A community summer event in which a large group of security bughunters (worldwide) collaborate in a month of security research on Open Source Software (WordPress this time). For fun. The event is hosted by Securify in Amsterdam.

OVE ID

OVE-20160731-0003

Tested versions

These issues were successfully tested on the All In One WP Security & Firewall WordPress Plugin version 4.1.4 - 4.1.9.

Fix

This issue has been addressed in All In One WP Security & Firewall version 4.2.0.

Introduction

All In One WP Security & Firewall is a comprehensive, user-friendly, all in one security and firewall plugin for WordPress. A Cross-Site Scripting vulnerability was found in the All In One WP Security & Firewall Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf.

Details

This issue exists in the file admin/wp-security-dashboard-menu.php and is caused due to the lack of output encoding on the tab request parameter.

<div class="inside">
   <?php
   //Fetch, prepare, sort, and filter our data...
   $locked_ip_list->prepare_items();
   //echo "put table of locked entries here";
   ?>
   <form id="tables-filter" method="get"
      onSubmit="return confirm('Are you sure you want to perform this bulk operation on the selected entries?');">
      <!-- For plugins, we also need to ensure that the form posts back to our current page -->
      <input type="hidden" name="page" value="<?php echo esc_attr($_REQUEST['page']); ?>"/>
      <?php
      if (isset($_REQUEST["tab"])) {
         echo '<input type="hidden" name="tab" value="' . $_REQUEST["tab"] . '" />';
      }
      ?>
      <!-- Now we can render the completed list table -->
      <?php $locked_ip_list->display(); ?>
   </form>
</div>

In order to exploit this issue, the attacker has to lure/force a logged on WordPress Administrator into opening a malicious website.

Proof of concept

<html>
   <body>
      <form action="http://<target>/wp-admin/admin.php?page=aiowpsec&tab=tab3" method="POST">
         <input type="hidden" name="tab" value="&quot;&gt;&lt;script&gt;alert&#40;1&#41;&lt;&#47;script&gt;" />
         <input type="submit" value="Submit request" />
      </form>
   </body>
</html>