HAX CMS PHP allows users to manage their microsite universe with a PHP backend. Prior to version 11.0.0, the application does not sufficiently sanitize user input, allowing for the execution of arbitrary JavaScript code. The 'saveNode' and 'saveManifest' endpoints take user input and store it in the JSON schema for the site. This content is then rendered in the generated HAX site. Although the application does not allow users to supply a script tag, it does allow the use of other HTML tags to run JavaScript. Version 11.0.0 fixes the issue.