MIT Kerberos 5 through 1.13.1 incorrectly expects that a krb5readmessage data field is represented as a string ending with a '\0' character, which allows remote attackers to cause a denial of service (NULL pointer dereference) via a zero-byte version string or cause a denial of service (out-of-bounds read) by omitting the '\0' character, related to appl/user_user/server.c and lib/krb5/krb/recvauth.c (CVE-2014-5355).