The virtnet_probe function in drivers/net/virtio_net.c in the Linux kernel before 4.2 attempts to support a FRAGLIST feature without proper memory allocation, which allows guest OS users to cause a denial of service (buffer overflow and memory corruption) via a crafted sequence of fragmented packets.
https://github.com/torvalds/linux/commit/48900cb6af4282fa0fb6ff4d72a81aa3dadb5c39
https://bugzilla.redhat.com/show_bug.cgi?id=1243852
http://www.ubuntu.com/usn/USN-2777-1
http://www.ubuntu.com/usn/USN-2774-1
http://www.ubuntu.com/usn/USN-2773-1
http://www.securitytracker.com/id/1034045
http://www.securityfocus.com/bid/76230
http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
http://www.debian.org/security/2015/dsa-3364
http://rhn.redhat.com/errata/RHSA-2016-0855.html
http://rhn.redhat.com/errata/RHSA-2015-1978.html
http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00018.html
http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00009.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-October/169378.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171454.html