Cross-site scripting (XSS) vulnerability in mail compose in Open-Xchange OX App Suite before 7.6.3-rev31, 7.8.x before 7.8.2-rev31, 7.8.3 before 7.8.3-rev41, and 7.8.4 before 7.8.4-rev28 allows remote attackers to inject arbitrary web script or HTML via the data-target attribute in an HTML page with data-toggle gadgets.