Red Hat Security Advisory 2015-0349-01 – KVM is a full virtualization solution for Linux on AMD64 and Intel 64 systems. The qemu-kvm packages provide the user-space component for running virtual machines using KVM. It was found that the Cirrus blit region checks were insufficient. A privileged guest user could use this flaw to write outside of VRAM-allocated buffer boundaries in the host’s QEMU process address space with attacker-provided data. An uninitialized data structure use flaw was found in the way the set_pixel_format() function sanitized the value of bits_per_pixel. An attacker able to access a guest’s VNC console could use this flaw to crash the guest.