Greenshift 11.4 - 11.4.5 - Authenticated (Subscriber+) Arbitrary File Upload

The Greenshift – animation and page builder blocks plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the gspb_make_proxy_api_request() 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.