This indicates an attack attempt to exploit a Denial Of Service vulnerability
in MIT Kerberos.
The vulnerability is caused by an error when the vulnerable software handles
a malicious request. Successful exploitation attempts will likely cause the program to crash, resulting in a Denial of Service condition.
MIT Kerberos 5 5-1.9
MIT Kerberos 5 1.9
Denial of Service: Remote attackers can crash vulnerable systems.
Apply the patch, available from the website.