AP Background 3.8.1 - 3.8.2 - Missing Authorization to Authenticated (Subscriber+) Arbitrary File Upload via advParallaxBackAdminSaveSlider Function

The AP Background plugin for WordPress is vulnerable to arbitrary file uploads due to missing authorization and insufficient file validation within the advParallaxBackAdminSaveSlider() handler in versions 3.8.1 to 3.8.2. 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.