Groundhogg <= 2.7.9.8 - Missing Authorization to Non-Arbitrary File Upload

The Groundhogg plugin for WordPress is vulnerable to unauthorized access of data and modification of data due to a missing capability check on the 'ajax_upload_file' function in versions up to, and including, 2.7.9.8. This makes it possible for authenticated attackers, with subscriber-level access and above, to upload a file to the contact, and then lists all the other uploaded files related to the contact.