A recently discovered DOM-based Reflected Cross-Site Scripting (XSS) vulnerability in Elementor's Elementor Website Builder plugin affects versions up to and including 3.5.5. This vulnerability, identified as CVE-2022-29455, allows attackers to inject malicious scripts into web pages viewed by other users, potentially leading to data theft, compromised accounts, or other harmful consequences.

References

- CVE-2022-29455
- Elementor Website Builder on WordPress Plugin Directory
- DOM-based XSS in Elementor Website Builder Advisory

Exploit Details

This vulnerability exists in the Elementor Website Builder plugin's handling of user-supplied URLs in the "Link" parameter of certain elements, such as buttons, icons, and image carousels. When rendering these elements, the plugin fails to properly sanitize the URL input from users. This allows an attacker to craft a malicious URL containing JavaScript code, which would then be executed in the victim user's browser when they visit the crafted URL.

Example Exploit

In this example, we will use an arbitrary alert message as the payload to showcase the impact of this vulnerability:

Payload: javascript:alert('XSS')

To exploit this vulnerability, an attacker could create a button using the Elementor Website Builder plugin and set the "Link" value to the payload. When another user visits the web page containing the malicious button and clicks on it, the JavaScript code in the payload will execute in their browser, displaying the alert message.

Here's a code snippet demonstrating the inclusion of the payload in a button element

<!-- Elementor button widget -->
<div class="elementor-widget-container">
   <div class="elementor-button-wrapper">
      <a href="javascript:alert('XSS')" class="elementor-button-link elementor-button" role="button">
         <span class="elementor-button-content-wrapper">
            <span class="elementor-button-text">Click me</span>
         </span>
      </a>
   </div>
</div>

Potential Impact

The impact of this vulnerability depends on the payload used by the attacker. In our example, the alert message is mostly harmless. However, more malicious payloads could be employed for various purposes. Attackers could access sensitive data, steal authentication cookies, deface the website, redirect users to phishing websites, or even exploit other vulnerabilities in the browser or on the website.

Mitigation

It is recommended that users of the Elementor Website Builder plugin update to the latest version, which addresses this vulnerability. Proper input validation and output encoding should also be implemented to prevent this type of attack from occurring again.

Developers can refer to the OWASP XSS Prevention Cheat Sheet for guidelines on how to securely handle user-supplied data and protect applications from XSS attacks.

Conclusion

The Elementor Website Builder plugin's DOM-based Reflected XSS vulnerability (CVE-2022-29455) in versions up to 3.5.5 poses a significant risk to both end users and website administrators. Updating the plugin to the latest version and following secure coding practices can help mitigate the potential harm inflicted by attackers exploiting this vulnerability.

Timeline

Published on: 06/13/2022 17:15:00 UTC
Last modified on: 06/27/2022 16:18:00 UTC