Starter Templates <= 4.4.41 - Authenticated (Author+) Arbitrary File Upload via WXR Upload Bypass

The Starter Templates plugin for WordPress is vulnerable to arbitrary file upload in all versions up to, and including, 4.4.41. This is due to insufficient file type validation detecting WXR files, allowing double extension files to bypass sanitization while being accepted as a valid WXR file. 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.