Hustle <= 7.8.9.2 - Authenticated (Subscriber+) Arbitrary File Upoload via Module Import

The Hustle – Email Marketing, Lead Generation, Optins, Popups plugin for WordPress is vulnerable to arbitrary file uploads due to incorrect file type validation in the action_import_module() function in all versions up to, and including, 7.8.9.2. This makes it possible for authenticated attackers, with a lower-privileged role (e.g., Subscriber-level access and above), to upload arbitrary files on the affected site's server which may make remote code execution possible. Successful exploitation requires an admin to grant Hustle module permissions (or module edit access) to the low-privileged user so they can access the Hustle admin page and obtain the required nonce.