Kerberos 4 KDC program does not properly check for null termination of AUTH_MSG_KDC_REQUEST requests, which allows remote attackers to cause a denial of service via a malformed request.
Buffer overflow in Kerberos IV compatibility libraries as used in Kerberos V allows local users to gain root privileges via a long line in a kerberos configuration file, which can be specified via the KRB_CONF environmental variable.