KVM (Kernel-based Virtual Machine) is a full virtualization solution forLinux on AMD64 and Intel 64 systems. qemu-kvm is the user-space componentfor running virtual machines using KVM.A flaw was found in the way qemu-kvm handled VSC_ATR messages when a guestwas configured for a CCID (Chip/Smart Card Interface Devices) USB smartcard reader in passthrough mode. An attacker able to connect to the port onthe host being used for such a device could use this flaw to crash theqemu-kvm process on the host or, possibly, escalate their privileges on thehost. (CVE-2011-4111)All users of qemu-kvm should upgrade to these updated packages, whichcontain a backported patch to resolve this issue. After installing thisupdate, shut down all running virtual machines. Once all virtual machineshave shut down, start them again for this update to take effect.