In Wireshark 2.6.0 to 2.6.4 and 2.4.0 to 2.4.10, the MMSE dissector could go into an infinite loop. This was addressed in epan/dissectors/packet-mmse.c by preventing length overflows.
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00027.html
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=15250
https://lists.debian.org/debian-lts-announce/2019/01/msg00010.html
https://www.debian.org/security/2018/dsa-4359