CVE-2026-40509OpenEMR before 8.3.0 contains a cross-site request forgery vulnerability in the DICOM viewer. The web_path GET parameter in the DICOM viewer page is embedded unsanitized as a URL without validation against expected path formats. An attacker can craft a URL that causes an authenticated user with Patients - Documents permissions to make authenticated requests to arbitrary OpenEMR endpoints, enabling forced logout and other state-changing actions.