OpenEMR before 8.3.0 contains an insecure direct object reference vulnerability in OnsiteDocumentController::Query() that allows authenticated portal patients to read other patients' documents by overriding Pid_Equals criteria. Attackers can supply Pid_Equals, Pid_GreaterThan, or Pid_In request parameters to the onsitedocuments API to retrieve signed consent forms, signatures, and PHI of any patient.
CWE-639