Admidio is an open-source user management solution. Prior to version 5.0.9, the ecard_preview.php endpoint does not validate that the ecard_template POST parameter is a safe filename before passing it to ECard::getEcardTemplate(). An authenticated user can supply a path traversal payload (e.g., ../config.php) to read arbitrary files accessible to the web server process, including adm_my_files/config.php which contains database credentials. This issue has been patched in version 5.0.9.