OpenEMR's Printable LBF Endpoint Leaks Arbitrary Patient Forms

OpenEMR is a free and open source electronic health records and medical practice management application. Prior to version 8.0.0, the Layout-Based Form (LBF) printable view accepts formid and visitid (or patientid) from the request and does not verify that the form belongs to the current user’s authorized patient/encounter. An authenticated user with LBF access can enumerate form IDs and view or print any patient’s encounter forms. Version 8.0.0 fixes the issue.