MailChimp for Woocommerce < 2.7.1 - Subscriber+ SSRF

The Mailchimp for WooCommerce WordPress plugin before 2.7.1 has an AJAX action that allows any logged in users (such as subscriber) to perform a POST request on behalf of the server to the internal network/LAN, the body of the request is also appended to the response so it can be used to scan private network for example