qemu - security update

Several vulnerabilities were discovered in qemu, a fast processor
emulator.

• CVE-2015-3209
  Matt Tait of Google’s Project Zero security team discovered a flaw
  in the way QEMU’s AMD PCnet Ethernet emulation handles multi-TMD
  packets with a length above 4096 bytes. A privileged guest user in a
  guest with an AMD PCNet ethernet card enabled can potentially use
  this flaw to execute arbitrary code on the host with the privileges
  of the hosting QEMU process.
• CVE-2015-4037
  Kurt Seifried of Red Hat Product Security discovered that QEMU’s
  user mode networking stack uses predictable temporary file names
  when the -smb option is used. An unprivileged user can use this flaw
  to cause a denial of service.
• CVE-2015-4103
  Jan Beulich of SUSE discovered that the QEMU Xen code does not
  properly restrict write access to the host MSI message data field,
  allowing a malicious guest to cause a denial of service.
• CVE-2015-4104
  Jan Beulich of SUSE discovered that the QEMU Xen code does not
  properly restrict access to PCI MSI mask bits, allowing a malicious
  guest to cause a denial of service.
• CVE-2015-4105
  Jan Beulich of SUSE reported that the QEMU Xen code enables
  logging for PCI MSI-X pass-through error messages, allowing a
  malicious guest to cause a denial of service.
• CVE-2015-4106
  Jan Beulich of SUSE discovered that the QEMU Xen code does not
  properly restrict write access to the PCI config space for certain
  PCI pass-through devices, allowing a malicious guest to cause a
  denial of service, obtain sensitive information or potentially
  execute arbitrary code.

For the oldstable distribution (wheezy), these problems have been fixed
in version 1.1.2+dfsg-6a+deb7u8. Only CVE-2015-3209 and CVE-2015-4037
affect oldstable.

For the stable distribution (jessie), these problems have been fixed in
version 1:2.1+dfsg-12+deb8u1.

For the unstable distribution (sid), these problems have been fixed in
version 1:2.3+dfsg-6.

We recommend that you upgrade your qemu packages.