The xorg-x11-drv-qxl package provides an X11 video driver for the QEMU QXL video accelerator. This driver makes it possible to use Red Hat Enterprise Linux 6 as a guest operating system under the KVM kernel module and the QEMU multi-platform emulator, using the SPICE protocol. A flaw was found in the way the host"s qemu-kvm qxl driver and the guest"s X.Org qxl driver interacted when a SPICE connection terminated. A user able to initiate a SPICE connection to a guest could use this flaw to make the guest temporarily unavailable or, potentially , crash the guest. All users of xorg-x11-drv-qxl are advised to upgrade to this updated package, which contains a backported patch to correct this issue. All running X.Org server instances using the qxl driver must be restarted for this update to take effect.