Silverstripe Framework is the Model-View-Controller framework that powers the Silverstripe content management system. Prior to version 4.12.15, an attacker can display a link to a third party website on a login screen by convincing a legitimate content author to follow a specially crafted link. Users should upgrade to Silverstripe Framework 4.12.15 or above to address the issue.

Open redirect vulnerability on CMSSecurity relogin screen