The remote host is missing an update to krb5 announced via advisory USN-755-1.
Details follow:
Multiple flaws were discovered in the Kerberos GSS-API and ASN.1 routines that did not correctly handle certain requests. An unauthenticated remote attacker could send specially crafted traffic to crash services using the Kerberos library, leading to a denial of service.
Solution: The problem can be corrected by upgrading your system to the following package versions: