OpenEMR before 8.3.0 contains a broken access control vulnerability in portal/portal_payment.php...

OpenEMR before 8.3.0 contains a broken access control vulnerability in portal/portal_payment.php that allows low-privilege authenticated users to bypass billing ACL checks by tampering patient identifiers. Attackers can modify the pid and form_pid parameters to view payment pages and record fraudulent payment receipts for arbitrary patients, corrupting billing records.