In Wireshark 3.2.0 to 3.2.6, 3.0.0 to 3.0.13, and 2.6.0 to 2.6.20, the MIME Multipart dissector could crash. This was addressed in epan/dissectors/packet-multipart.c by correcting the deallocation of invalid MIME parts.
https://www.wireshark.org/security/wnpa-sec-2020-11.html
https://www.oracle.com/security-alerts/cpujan2021.html
https://lists.debian.org/debian-lts-announce/2021/02/msg00008.html
https://gitlab.com/wireshark/wireshark/-/issues/16741
https://gitlab.com/wireshark/wireshark/-/commit/5803c7b87b3414cdb8bf502af50bb406ca774482
http://lists.opensuse.org/opensuse-security-announce/2020-11/msg00038.html
http://lists.opensuse.org/opensuse-security-announce/2020-11/msg00035.html