USN-2608-1: QEMU vulnerabilities

Publication date

13 May 2015

Overview

Several security issues were fixed in QEMU.


Packages

  • qemu - Machine emulator and virtualizer
  • qemu-kvm - Machine emulator and virtualizer

Details

Jason Geffner discovered that QEMU incorrectly handled the virtual floppy
driver. This issue is known as VENOM. A malicious guest could use this
issue to cause a denial of service, or possibly execute arbitrary code on
the host as the user running the QEMU process. In the default installation,
when QEMU is used with libvirt, attackers would be isolated by the libvirt
AppArmor profile. (CVE-2015-3456)

Daniel P. Berrange discovered that QEMU incorrectly handled VNC websockets.
A remote attacker could use this issue to cause QEMU to consume memory,
resulting in a denial of service. This issue only affected Ubuntu 14.04
LTS, Ubuntu 14.10 and Ubuntu 15.04. (CVE-2015-1779)

Jan Beulich discovered that QEMU, when used with Xen, didn’t properly
restrict access to PCI command registers. A malicious guest could use this
issue to cause a denial of service. This...

Jason Geffner discovered that QEMU incorrectly handled the virtual floppy
driver. This issue is known as VENOM. A malicious guest could use this
issue to cause a denial of service, or possibly execute arbitrary code on
the host as the user running the QEMU process. In the default installation,
when QEMU is used with libvirt, attackers would be isolated by the libvirt
AppArmor profile. (CVE-2015-3456)

Daniel P. Berrange discovered that QEMU incorrectly handled VNC websockets.
A remote attacker could use this issue to cause QEMU to consume memory,
resulting in a denial of service. This issue only affected Ubuntu 14.04
LTS, Ubuntu 14.10 and Ubuntu 15.04. (CVE-2015-1779)

Jan Beulich discovered that QEMU, when used with Xen, didn’t properly
restrict access to PCI command registers. A malicious guest could use this
issue to cause a denial of service. This issue only affected Ubuntu 14.04
LTS and Ubuntu 14.10. (CVE-2015-2756)


Update instructions

After a standard system update you need to restart all QEMU virtual machines to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:


Reduce your security exposure

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