The instruction decoder in arch/x86/kvm/emulate.c in the KVM subsystem in the Linux kernel before 3.18-rc2 lacks intended decoder-table flags for certain RIP-relative instructions, which allows guest OS users to cause a denial of service (NULL pointer dereference and host OS crash) via a crafted application. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-8480