In Wireshark 2.4.0 to 2.4.5 and 2.2.0 to 2.2.13, the Kerberos dissector could crash. This was addressed in epan/dissectors/packet-kerberos.c by ensuring a nonzero key length.
https://www.wireshark.org/security/wnpa-sec-2018-23.html
https://lists.debian.org/debian-lts-announce/2019/01/msg00010.html
https://lists.debian.org/debian-lts-announce/2018/05/msg00019.html