In Wireshark 2.4.0 to 2.4.13, 2.6.0 to 2.6.7, and 3.0.0, the GSS-API dissector could crash. This was addressed in epan/dissectors/packet-gssapi.c by ensuring that a valid dissector is called.
https://www.wireshark.org/security/wnpa-sec-2019-14.html
https://usn.ubuntu.com/3986-1/
https://lists.debian.org/debian-lts-announce/2020/10/msg00036.html
https://lists.debian.org/debian-lts-announce/2019/05/msg00034.html
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=15613
http://www.securityfocus.com/bid/107834
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00027.html
http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00027.html
http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00022.html