qemu-kvm is vulnerable to arbitrary code execution. The vulnerability exists as it was found that the PIIX4 Power Management emulation layer in qemu-kvm did not properly check for hot plug eligibility during device removals. A privileged guest user could use this flaw to crash the guest or, possibly, execute arbitrary code on the host.
blog.nelhage.com/2011/08/breaking-out-of-kvm/
docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html-single/6.1_Technical_Notes/index.html
git.kernel.org/?p=virt/kvm/qemu-kvm.git%3Ba=commit%3Bh=505597e4476a6bc219d0ec1362b760d71cb4fdca
git.kernel.org/?p=virt/kvm/qemu-kvm.git;a=commit;h=505597e4476a6bc219d0ec1362b760d71cb4fdca
lists.nongnu.org/archive/html/qemu-devel/2011-05/msg01810.html
lists.opensuse.org/opensuse-updates/2011-05/msg00043.html
rhn.redhat.com/errata/RHSA-2011-0534.html
secunia.com/advisories/44393
secunia.com/advisories/44458
secunia.com/advisories/44648
secunia.com/advisories/44658
secunia.com/advisories/44660
secunia.com/advisories/44900
www.openwall.com/lists/oss-security/2011/05/19/2
www.osvdb.org/73395
www.securityfocus.com/bid/47927
access.redhat.com/errata/RHSA-2011:0534
access.redhat.com/security/cve/CVE-2011-1751
access.redhat.com/security/updates/classification/#important
bugzilla.redhat.com/show_bug.cgi?id=699773
github.com/nelhage/virtunoid
hermes.opensuse.org/messages/8572547
www.ubuntu.com/usn/USN-1145-1/