Authorization Bypass Through User-Controlled Key in Prospero Flow CRM calendar event deletion (CVE-2026-59234)
CVE number = CVE-2026-59234
Authorization Bypass Through User-Controlled Key (CWE-639) in CalendarDeleteEventController (app/Http/Controllers/Calendar/CalendarDeleteEventController.php), exposed at GET /calendar/event/delete/{id}, in Prospero Flow CRM before 5.5.3.
This allows a remote, authenticated attacker to delete arbitrary calendar events belonging to other users by manipulating the {id} path parameter, because the delete handler resolves the record with Calendar::find($id)->delete() and performs no ownership check (no user_id/company_id scoping) before deletion. This results in unauthorized destruction of other users’ calendar events across the platform.
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