The Grav Data Manager plugin (getgrav/grav-plugin-datamanager) versions 1.0.1 through 1.4.4 render stored data entries in the item-detail view (admin/templates/partials/item.html.twig) without escaping, applying Twig's `raw` filter — in some cases after a striptags('<br>') call that PHP's strip_tags() bypasses by preserving allowed tags together with their attributes. An unauthenticated visitor who submits a front-end form whose submissions are saved to user/data can store an HTML payload that executes as JavaScript in the session and origin of an administrator who later opens that entry in the classic admin panel, running with that administrator's privileges and CSRF token. Execution occurs without further interaction for list values (such as checkbox or multi-select fields) and on hover for ordinary text fields.
Sites using the Grav 2.0 Admin Next interface are not affected, because it renders the same data through a separate, correctly escaping code path. The issue is fixed in Data Manager 1.4.5.
Attack Parameters
Impact Assessment
CVSS Vector v4.0