XSS in Authentik via JavaScript-URI as Redirect URI and form_post Response Mode

Authentik is an open-source Identity Provider. Authentik is a vulnerable to a reflected Cross-Site Scripting vulnerability via JavaScript-URIs in OpenID Connect flows with `response_mode=form_post`. This relatively user could use the described attacks to perform a privilege escalation. This vulnerability has been patched in versions 2023.10.6 and 2023.8.6.