Multiple cross-site scripting (XSS) vulnerabilities in Horde Groupware, Groupware Webmail Edition, and Kronolith allow remote attackers to inject arbitrary web script or HTML via the timestamp parameter to (1) week.php, (2) workweek.php, and (3) day.php; and (4) the horde parameter in the PATH_INFO to the default URI.  NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.