KiotViet Sync <= 1.8.5 - Use of Hard-coded Password to Authorization Bypass

The KiotViet Sync plugin for WordPress is vulnerable to authorizarion bypass in all versions up to, and including, 1.8.5. This is due to the plugin using a hardcoded password for authentication in the QueryControllerAdmin::authenticated function. This makes it possible for unauthenticated attackers to create and sync products.