Cross-site scripting (XSS) vulnerability in the backend in Open-Xchange (OX) AppSuite before 7.4.2-rev40, 7.6.0 before 7.6.0-rev32, and 7.6.1 before 7.6.1-rev11 allows remote attackers to inject arbitrary web script or HTML via a crafted XHTML file with the application/xhtml+xml MIME type.