arch/x86/kvm/vmx.c in the KVM subsystem in the Linux kernel before 3.12 does not have an exit handler for the INVEPT instruction, which allows guest OS users to cause a denial of service (guest OS crash) via a crafted application.
https://github.com/torvalds/linux/commit/bfd0a56b90005f8c8a004baf407ad90045c2b11e
https://bugzilla.redhat.com/show_bug.cgi?id=1144835
http://www.ubuntu.com/usn/USN-2418-1
http://www.ubuntu.com/usn/USN-2417-1
http://www.openwall.com/lists/oss-security/2014/10/24/9
http://www.debian.org/security/2014/dsa-3060
http://rhn.redhat.com/errata/RHSA-2015-0284.html