OS DataHub Maps <= 1.8.3 - Authenticated (Author+) Arbitrary File Upload

The OS DataHub Maps plugin for WordPress is vulnerable to arbitrary file uploads due to incorrect file type validation in the 'OS_DataHub_Maps_Admin::add_file_and_ext' function in all versions up to, and including, 1.8.3. This makes it possible for authenticated attackers, with Author-level access and above, to upload arbitrary files on the affected site's server which may make remote code execution possible.