Use-after-free vulnerability in hw/pci/pcie.c in QEMU (aka Quick Emulator) allows local guest OS users to cause a denial of service (QEMU instance crash) via hotplug and hotunplug operations of Virtio block devices.
https://lists.gnu.org/archive/html/qemu-devel/2014-06/msg05283.html
https://bugzilla.redhat.com/show_bug.cgi?id=1112271
http://www.securityfocus.com/bid/68145