CentOS Errata and Security Advisory CESA-2015:1943
KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on AMD64 and Intel 64 systems. The qemu-kvm package provides the user-space component for running virtual machines using KVM.
It was found that the QEMU's websocket frame decoder processed incoming frames without limiting resources used to process the header and the payload. An attacker able to access a guest's VNC console could use this flaw to trigger a denial of service on the host by exhausting all available memory and CPU. (CVE-2015-1779)
This issue was discovered by Daniel P. Berrange of Red Hat.
All qemu-kvm users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue. After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.
Merged security bulletin from advisories: http://lists.centos.org/pipermail/centos-announce/2015-October/033487.html
Affected packages: libcacard libcacard-devel libcacard-tools qemu-img qemu-kvm qemu-kvm-common qemu-kvm-tools
Upstream details at: https://rhn.redhat.com/errata/RHSA-2015-1943.html