The remote host is missing an update to sylpheed-claws announced via advisory DSA 908-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20908-1

Colin Leroy discovered several buffer overflows in a number of importer routines in sylpheed-claws, an extended version of the Sylpheed mail client, that could lead to the execution of arbitrary code. The following matrix explains which versions fix this vulnerability old stable (woody) stable (sarge) unstable (sid) sylpheed 0.7.4-4woody1 1.0.4-1sarge1 2.0.4-1 sylpheed-gtk1 n/a n/a 1.0.6-1 sylpheed-claws 0.7.4claws-3woody1 1.0.4-1sarge1 1.0.5-2 sylpheed-claws-gtk2 n/a n/a 1.9.100-1 We recommend that you upgrade your sylpheed-claws package.