WordPress User Extra Fields <= 16.5 - Unauthenticated Arbitrary File Upload

The WordPress User Extra Fields plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the ajax_manage_file_chunk_upload() function in all versions up to, and including, 16.5. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. User registration must be enabled for this to be exploited.