A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows crafted packets to cause a denial of service.
https://www.debian.org/security/2020/dsa-4665
https://usn.ubuntu.com/4372-1/
https://lists.debian.org/debian-lts-announce/2020/07/msg00020.html
https://lists.debian.org/debian-lts-announce/2020/06/msg00032.html
https://gitlab.freedesktop.org/slirp/libslirp/-/issues/20
https://gitlab.freedesktop.org/slirp/libslirp/-/commit/9ac0371bb8c0a40f5d9f82a1c25129660e81df04
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00001.html
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00022.html