Embed PDF for WPForms <= 1.1.5 - Authenticated (Subscriber+) Arbitrary File Upload

The Embed PDF for WPForms plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the ajax_handler_download_pdf_media function in all versions up to, and including, 1.1.5. This makes it possible for authenticated attackers, with Subscriber-level access and above, to upload arbitrary files on the affected site's server which may make remote code execution possible.