CKEditor4 is a widely used open-source WYSIWYG HTML editor that offers excellent performance and a myriad of features. However, a potential vulnerability (CVE-2024-43407) has been discovered in the CKEditor 4 Code Snippet GeSHi plugin. This vulnerability allows a reflected XSS attack to exploit a flaw in the GeSHi syntax highlighter library (https://github.com/easybook/geshi) hosted by the victim. As a result, this vulnerability poses a significant security risk for users of CKEditor 4 with the GeSHi plugin enabled.

The GeSHi library is included as a vendor dependency in CKEditor 4 source files. In a specific scenario, an attacker could craft a malicious script that, when executed, could send a request to the GeSHi library hosted on a PHP web server. Here is a code snippet illustrating the potential exploit:

// Malicious script example
$payload = '<img src="x" onerror=';
$payload .= urlencode('/* arbitrary JavaScript code */');
$url = "https://victimserver.com/path/to/geshi-library.php";;
$url .= "?lang=javascript&source=$payload";

As the GeSHi library is no longer actively maintained, its continued use poses risks due to the lack of ongoing support and updates. Consequently, potential security vulnerabilities could arise from its use in CKEditor 4.

As a proactive measure for enhancing the overall security of CKEditor 4 and mitigating the risks posed by the GeSHi library, we have decided to completely remove the GeSHi library as a dependency. By doing so, we aim to maintain a secure environment and reduce the risk of any security incidents related to outdated or unsupported software.

We encourage all CKEditor 4 users to update the editor to version 4.25.-lts (https://github.com/ckeditor/ckeditor4/releases/tag/4.25.) as the fix for this vulnerability is available in this version. We also recommend users to thoroughly evaluate their usage of third-party plugins and dependencies to ensure their compliance with security best practices and up-to-date maintenance.

It is essential to ensure that web applications are secure and free from vulnerabilities. By addressing CVE-2024-43407, we intend to contribute to safeguarding the CKEditor 4 user community and providing a secure platform for HTML editing. Stay vigilant and protect your applications from potential security threats!

Timeline

Published on: 08/21/2024 15:15:09 UTC
Last modified on: 08/23/2024 16:20:42 UTC