Several security issues were fixed in QEMU.
Laszlo Ersek discovered that QEMU incorrectly handled memory in the vga device. A malicious guest could possibly use this issue to read arbitrary host memory. This issue only affected Ubuntu 14.04 LTS and Ubuntu 14.10. (CVE-2014-3615)
13 November 2014
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in QEMU.
Laszlo Ersek discovered that QEMU incorrectly handled memory in the vga device. A malicious guest could possibly use this issue to read arbitrary host memory. This issue only affected Ubuntu 14.04 LTS and Ubuntu 14.10. (CVE-2014-3615)
Xavier Mehrenberger and Stephane Duverger discovered that QEMU incorrectly handled certain udp packets when using guest networking. A malicious guest could possibly use this issue to cause a denial of service. (CVE-2014-3640)
It was discovered that QEMU incorrectly handled parameter validation in the vmware_vga device. A malicious guest could possibly use this issue to write into memory of the host, leading to privilege escalation. (CVE-2014-3689)
It was discovered that QEMU incorrectly handled USB xHCI controller live migration. An attacker could possibly use this issue to cause a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 14.04 LTS. (CVE-2014-5263)
Michael S. Tsirkin discovered that QEMU incorrectly handled memory in the ACPI PCI hotplug interface. A malicious guest could possibly use this issue to access memory of the host, leading to information disclosure or privilege escalation. This issue only affected Ubuntu 14.04 LTS. (CVE-2014-5388)
James Spadaro discovered that QEMU incorrectly handled certain VNC bytes_per_pixel values. An attacker having access to a VNC console could possibly use this issue to cause a guest to crash, resulting in a denial of service. (CVE-2014-7815)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.