@webiny/react-rich-text-renderer before 5.37.2 allows XSS attacks by content managers. This is a react component to render data coming from Webiny Headless CMS and Webiny Form Builder. Webiny is an open-source serverless enterprise CMS. The @webiny/react-rich-text-renderer package depends on the editor.js rich text editor to handle rich text content. The CMS stores rich text content from the editor.js into the database. When the @webiny/react-rich-text-renderer is used to render such content, it uses the dangerouslySetInnerHTML prop, without applying HTML sanitization. The issue arises when an actor, who in this context would specifically be a content manager with access to the CMS, inserts a malicious script as part of the user-defined input. This script is then injected and executed within the user's browser when the main page or admin page loads.