USN-1165-1: QEMU vulnerabilities

Ubuntu Security Notice USN-1165-1

6th July, 2011

qemu-kvm vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 11.04
  • Ubuntu 10.10
  • Ubuntu 10.04 LTS

Summary

A privileged attacker within a QEMU guest could cause QEMU to crash.

Software description

  • qemu-kvm - Machine emulator and virtualizer

Details

Nelson Elhage discoverd that QEMU did not properly validate certain
virtqueue requests from the guest. An attacker could exploit this to cause
a denial of service of the guest or possibly execute code with the
privileges of the user invoking the program. (CVE-2011-2212)

Stefan Hajnoczi discovered that QEMU did not properly perform integer
comparisons when performing virtqueue input validation. An attacker could
exploit this to cause a denial of service of the guest or possibly execute
code with the privileges of the user invoking the program. (CVE-2011-2512)

When using QEMU with libvirt or virtualization management software based on
libvirt such as Eucalyptus and OpenStack, QEMU guests are individually
isolated by an AppArmor profile by default in Ubuntu.

Update instructions

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

Ubuntu 11.04:
qemu-kvm 0.14.0+noroms-0ubuntu4.3
Ubuntu 10.10:
qemu-kvm 0.12.5+noroms-0ubuntu7.8
qemu-kvm-extras-static 0.12.5+noroms-0ubuntu7.8
qemu-kvm-extras 0.12.5+noroms-0ubuntu7.8
Ubuntu 10.04 LTS:
qemu-kvm 0.12.3+noroms-0ubuntu9.12
qemu-kvm-extras-static 0.12.3+noroms-0ubuntu9.12
qemu-kvm-extras 0.12.3+noroms-0ubuntu9.12

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

References

CVE-2011-2212, CVE-2011-2512