Silverstripe Framework is a PHP framework which powers the Silverstripe CMS. In versions prior to 6.2.2, the "Insert media from web" functionality in the CMS is vulnerable to XSS from a specially crafted embed. This issue was fixed in version 6.2.2/
https://www.silverstripe.org/download/security-releases/cve-2026-54720
https://github.com/silverstripe/silverstripe-framework/security/advisories/GHSA-gvrw-qqp5-jgc5