qemu/qemu_monitor.c in libvirt allows attackers to cause a denial of service (memory consumption) via a large QEMU reply.
https://www.redhat.com/archives/libvir-list/2018-January/msg00527.html
https://www.debian.org/security/2018/dsa-4137
https://lists.debian.org/debian-lts-announce/2018/03/msg00018.html
https://access.redhat.com/errata/RHSA-2018:1929