The remote host is missing an update to krb5 announced via advisory DSA 629-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20629-1

A buffer overflow has been discovered in the MIT Kerberos 5 administration library (libkadm5srv) that could lead to the execution of arbitrary code upon exploition by an authenticated user, not necessarily one with administrative privileges. For the stable distribution (woody) this problem has been fixed in version 1.2.4-5woody7. For the unstable distribution (sid) this problem has been fixed in version 1.3.6-1. We recommend that you upgrade your krb5 packages.