The remote host is missing an update to libtheora announced via advisory DSA 2045-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202045-1

Bob Clary, Dan Kaminsky and David Keeler discovered that in libtheora, a video library part of the Ogg project, several flaws allow allow context-dependent attackers via a large and specially crafted media file, to cause a denial of service (crash of the player using this library), and possibly arbitrary code execution. For the stable distribution (lenny), this problem has been fixed in version 1.0~beta3-1+lenny1. For the testing distribution (squeeze), this problem has been fixed in version 1.1.0-1. For the testing distribution (sid), this problem has been fixed in version 1.1.0-1. We recommend that you upgrade your libtheora packages.