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.
MD5 checksums of the listed files are available in the original advisory.