Overview: Amasty Blog version 2.10.3, a popular extension for e-commerce stores, has been found to be vulnerable to a Cross Site Scripting (XSS) attack. This issue can be exploited via the 'leave comment' functionality of the module, which can potentially allow malicious users to execute harmful scripts on your website. In this post, we will be providing a detailed look at the vulnerability, links to original references, and code snippets to help understand and mitigate the risk.

Vulnerability Details

Cross Site Scripting (XSS) can enable an attacker to inject and execute malicious scripts on web pages viewed by other users, an action that may lead to various security risks such as data theft, exploitation, phishing, or defacing of the targeted website.

Amasty Blog version 2.10.3 has a leave comment functionality that is not properly validating user input. This improper validation allows malicious users to insert and execute JavaScript code within the comment field, thus potentially compromising the security of your website and negatively affecting user experience.

To illustrate the vulnerability, here is a proof of concept (PoC) code snippet

<form action="http://example.com/amasty_blog/comment/post/id/1"; method="post" id="comment-form">
  <input type="hidden" name="form_key" value="FORM_KEY" />
  <input type="text" name="name" value="John Doe" />
  <input type="email" name="email" value="email@example.com" />
  <textarea name="comment">Hello world! <script>alert('XSS')</script></textarea>
  <input type="submit" value="Submit comment" />
</form>

In this example, a comment containing a malicious script <script>alert('XSS')</script> is submitted. When the comment is displayed on the website, the script will execute, displaying a simple alert box with the text 'XSS'.

Exploit Mitigation

To mitigate this vulnerability, it is essential to validate user input and sanitize any data received from untrusted sources. In the case of Amasty Blog, you should update the plugin to a secure version or apply a patch provided by the developer. Additionally, you should also consider implementing Content Security Policy (CSP), which can help prevent the execution of malicious scripts.

References

1. CVE-2022-35500
2. Amasty Blog

Conclusion

The Cross Site Scripting (XSS) vulnerability found in Amasty Blog version 2.10.3 highlights the importance of proper input validation and sanitization when dealing with user-generated data. It is imperative to keep all software up-to-date and apply security patches whenever available. By taking the necessary precautions and implementing proper security measures, you can significantly reduce the risks associated with such vulnerabilities and maintain a safer web environment for your users.

Timeline

Published on: 11/23/2022 02:15:00 UTC
Last modified on: 11/28/2022 15:26:00 UTC