CKEditor4 is an open source what-you-see-is-what-you-get HTML editor. A theoretical vulnerability has been identified in CKEditor 4.22 (and above). In a highly unlikely scenario where an attacker gains control over the https://cke4.ckeditor.com domain, they could potentially execute an attack on CKEditor 4 instances. The issue impacts only editor instances with enabled version notifications. Please note that this feature is disabled by default in all CKEditor 4 LTS versions. Therefore, if you use CKEditor 4 LTS, it is highly unlikely that you are affected by this vulnerability. If you are unsure, please contact us. The fix is available in version 4.25.0-lts.