The virtio_net_bad_features function in hw/virtio-net.c in the virtio-net driver in the Linux kernel before 2.6.26, when used on a guest OS in conjunction with qemu-kvm 0.11.0 or KVM 83, allows remote attackers to cause a denial of service (guest OS crash, and an associated qemu-kvm process exit) by sending a large amount of network traffic to a TCP port on the guest OS, related to a virtio-net whitelist that includes an improper implementation of TCP Segment Offloading (TSO).
http://lists.gnu.org/archive/html/qemu-devel/2009-10/msg02480.html
http://lists.gnu.org/archive/html/qemu-devel/2009-10/msg02495.html
http://openwall.com/lists/oss-security/2010/03/29/4
https://bugs.edge.launchpad.net/ubuntu/+source/qemu-kvm/+bug/458521
https://bugzilla.redhat.com/show_bug.cgi?id=577218
http://securitytracker.com/id?1023798
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11143
https://patchwork.kernel.org/patch/56479/
https://rhn.redhat.com/errata/RHSA-2010-0476.html