The Greenshift – animation and page builder blocks plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the gspbmakeproxyapirequest() function in versions 11.4 to 11.4.5. 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. The arbitrary file upload was sufficiently patched in 11.4.5, but a capability check was added in 11.4.6 to properly prevent unauthorized limited file uploads.