The GutenKit WordPress plugin before 2.5.0 does not sanitise uploaded SVG files on all of the upload paths it enables, allowing users with the file upload capability, such as Author, to upload a malicious SVG and perform Stored Cross-Site Scripting attacks against any user opening it, including administrators.

The GutenKit Blocks plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the /wp-json/gutenkit/v1/mailchimp/get/lists and /wp-json/gutenkit/v1/mailchimp/get/interests REST API endpoints in versions up to, and including, 2.4.12. Both endpoints are registered with permissioncallback => 'returntrue', and their callbacks read the site's stored Mailchimp API key from the gutenkitsettingslist option and proxy Mailchimp audience/list, merge-field, interest-category, interest-name, and subscriber-count metadata back to the caller with no login, nonce, or capability check. This makes it possible for unauthenticated attackers to retrieve private Mailchimp audience configuration information from any site that has configured the GutenKit Mailchimp integration.

The GutenKit – Page Builder Blocks, Patterns, and Templates for Gutenberg Block Editor plugin for WordPress is vulnerable to arbitrary file uploads due to a missing capability check on the installandactivatepluginfromexternal() function (install-active-plugin REST API endpoint) in all versions up to, and including, 2.1.0. This makes it possible for unauthenticated attackers to install and activate arbitrary plugins, or utilize the functionality to upload arbitrary files spoofed like plugins.