Cross-site scripting (XSS) vulnerability in the Easy MailChimp Forms plugin 3.0 through 5.0.6 for WordPress allows remote attackers to inject arbitrary web script or HTML via the updateoptions action to wp-admin/admin-ajax.php.

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

The Block For Mailchimp – Easy Mailchimp Form Integration plugin for WordPress is vulnerable to Blind Server-Side Request Forgery in all versions up to, and including, 1.1.12 via the mcbSubmitFormData(). This makes it possible for unauthenticated attackers to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.

The Mailchimp for WooCommerce WordPress plugin before 2.7.2 has an AJAX action that allows high privilege users 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

The Mailchimp for WooCommerce WordPress plugin before 6.1.1 does not verify that the requesting user holds the required capability in the permission callback for several of its REST API routes, allowing unauthenticated users to reach administrator-oriented endpoints and trigger a persistent state change.