The remote host is missing an update to webcalendar announced via advisory DSA 1096-1. A vulnerability has been discovered in webcalendar, a PHP-based multi-user calendar, that allows a remote attacker to execute arbitrary PHP code when register_globals is turned on. The old stable distribution (woody) does not contain a webcalendar package.
For the stable distribution (sarge) this problem has been fixed in version 0.9.45-4sarge5. For the unstable distribution (sid) this problem has been fixed in version 1.0.4-1 We recommend that you upgrade your webcalendar package. https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201096-1