The remote host is missing an update to the system as announced in the referenced advisory FreeBSD-SA-04:09.kadmind.asc

Upgrade your system to the appropriate stable release or security branch dated after the correction date https://secure1.securityspace.com/smysecure/catid.html?in=FreeBSD-SA-04:09.kadmind.asc

Heimdal implements the Kerberos 5 network authentication protocols. The k5admind(8) daemon provides the administrative interface to the Kerberos Key Distribution Center (KDC). In some configurations, k5admind also includes Kerberos 4 compatibility. NOTE: FreeBSD versions prior to 5.1-RELEASE contain optional Kerberos 4 support. FreeBSD versions 5.1-RELEASE and later do not include Kerberos 4 support of any kind. An input validation error was discovered in the k5admind code that handles the framing of Kerberos 4 compatibility administration requests. The code assumed that the length given in the framing was always two or more bytes. Smaller lengths will cause k5admind to read an arbitrary amount of data into a minimally-sized buffer on the heap. Note that this code is not present unless k5admind has been compiled with Kerberos 4 support. This will occur if a FreeBSD system is compiled with both of the WITH_KERBEROS4 and WITH_KERBEROS5 build flags. These flags are never simultaneously set during the FreeBSD binary release process consequently, binary installs of FreeBSD (even with Kerberos support installed) are not affected.