The remote host is missing an update to ctorrent announced via advisory DSA 1817-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201817-1

Michael Brooks discovered that ctorrent, a text-mode bittorrent client, does not verify the length of file paths in torrent files. An attacker can exploit this via a crafted torrent that contains a long file path to execute arbitrary code with the rights of the user opening the file. The oldstable distribution (etch) does not contain ctorrent. For the stable distribution (lenny), this problem has been fixed in version 1.3.4-dnh3.2-1+lenny1. For the testing distribution (squeeze), this problem will be fixed soon. For the unstable distribution (sid), this problem has been fixed in version 1.3.4-dnh3.2-1.1. We recommend that you upgrade your ctorrent packages.