CVE-2026-68526 Concrete CMS before 9.5.3 is vulnerable to CSRF in the Calendar event duplicate dialog controller

Concrete CMS before 9.5.3 did not validate an anti-CSRF token in the Calendar event duplicate dialog controller concrete/controllers/dialog/event/duplicate.php submit action, which duplicated a calendar event after checking only canAccess and the per-resource canAddCalendarEvent permission, so a...