neos/forms is an open source framework to build web forms. By crafting a special `GET` request containing a valid form state, a form can be submitted without invoking any validators. Form state is secured with an HMAC that is still verified. That means that this issue can only be exploited if Form Finishers cause side effects even if no form values have been sent. Form Finishers can be adjusted in a way that they only execute an action if the submitted form contains some expected data. Alternatively a custom Finisher can be added as first finisher. This regression was introduced with https://github.com/neos/form/commit/049d415295be8d4a0478ccba97dba1bb81649567

Multiple cross-site scripting (XSS) vulnerabilities in Neos CMS allow attackers with the editor role or higher to inject arbitrary script or HTML code using the editor function, the deletion of assets, or a workspace title. The vulnerabilities were found in versions 3.3.29 and 8.0.1 and could also be present in all intermediate versions.

Cross Site Scripting (XSS) vulnerability in Neos CMS 8.3.3 allows a remote authenticated attacker to execute arbitrary code via a crafted SVG file to the neos/management/media component.