The remote host is missing an update to krb5 announced via advisory DSA 2379-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202379-1

It was discovered that the Key Distribution Center (KDC) in Kerberos 5 crashes when processing certain crafted requests: CVE-2011-1528 When the LDAP backend is used, remote users can trigger a KDC daemon crash and denial of service. CVE-2011-1529 When the LDAP or Berkeley DB backend is used, remote users can trigger a NULL pointer dereference in the KDC daemon and a denial of service. The oldstable distribution (lenny) is not affected by these problems. For the stable distribution (squeeze), these problems have been fixed in version 1.8.3+dfsg-4squeeze5. For the testing distribution (wheezy) and the unstable distribution (sid), these problems have been fixed in version 1.10+dfsg~alpha1-1. We recommend that you upgrade your krb5 packages.