The Easy Digital Downloads – Simple eCommerce for Selling Digital Files plugin for WordPress is vulnerable to deserialization of untrusted input via the 'upload[file]' parameter in versions up to, and including 3.3.3. This makes it possible for authenticated administrative users to call files using a PHAR wrapper, that will deserialize and call arbitrary PHP Objects that can be used to perform a variety of malicious actions granted a POP chain is also present.