==========================================================================
Ubuntu Security Notice USN-4191-1
November 14, 2019

qemu vulnerabilities
==========================================================================

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

- Ubuntu 19.10
- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in QEMU.

Software Description:
- qemu: Machine emulator and virtualizer

Details:

It was discovered that the LSI SCSI adapter emulator implementation in QEMU
did not properly validate executed scripts. A local attacker could use this
to cause a denial of service. (CVE-2019-12068)

Sergej Schumilo, Cornelius Aschermann and Simon Wörner discovered that the
qxl paravirtual graphics driver implementation in QEMU contained a null
pointer dereference. A local attacker in a guest could use this to cause a
denial of service. (CVE-2019-12155)

Riccardo Schirone discovered that the QEMU bridge helper did not properly
validate network interface names. A local attacker could possibly use this
to bypass ACL restrictions. (CVE-2019-13164)

It was discovered that a heap-based buffer overflow existed in the SLiRP
networking implementation of QEMU. A local attacker in a guest could use
this to cause a denial of service or possibly execute arbitrary code in the
host. (CVE-2019-14378)

It was discovered that a use-after-free vulnerability existed in the SLiRP
networking implementation of QEMU. A local attacker in a guest could use
this to cause a denial of service. (CVE-2019-15890)

Update instructions:

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

Ubuntu 19.10:
  qemu                            1:4.0+dfsg-0ubuntu9.1
  qemu-kvm                        1:4.0+dfsg-0ubuntu9.1
  qemu-system-common              1:4.0+dfsg-0ubuntu9.1
  qemu-system-gui                 1:4.0+dfsg-0ubuntu9.1
  qemu-system-x86                 1:4.0+dfsg-0ubuntu9.1
  qemu-user-static                1:4.0+dfsg-0ubuntu9.1
  qemu-utils                      1:4.0+dfsg-0ubuntu9.1

Ubuntu 19.04:
  qemu                            1:3.1+dfsg-2ubuntu3.6
  qemu-kvm                        1:3.1+dfsg-2ubuntu3.6
  qemu-system-common              1:3.1+dfsg-2ubuntu3.6
  qemu-system-gui                 1:3.1+dfsg-2ubuntu3.6
  qemu-system-x86                 1:3.1+dfsg-2ubuntu3.6
  qemu-user-static                1:3.1+dfsg-2ubuntu3.6
  qemu-utils                      1:3.1+dfsg-2ubuntu3.6

Ubuntu 18.04 LTS:
  qemu                            1:2.11+dfsg-1ubuntu7.20
  qemu-kvm                        1:2.11+dfsg-1ubuntu7.20
  qemu-system-common              1:2.11+dfsg-1ubuntu7.20
  qemu-system-x86                 1:2.11+dfsg-1ubuntu7.20
  qemu-user-static                1:2.11+dfsg-1ubuntu7.20
  qemu-utils                      1:2.11+dfsg-1ubuntu7.20

Ubuntu 16.04 LTS:
  qemu                            1:2.5+dfsg-5ubuntu10.42
  qemu-kvm                        1:2.5+dfsg-5ubuntu10.42
  qemu-system-common              1:2.5+dfsg-5ubuntu10.42
  qemu-system-x86                 1:2.5+dfsg-5ubuntu10.42
  qemu-user-static                1:2.5+dfsg-5ubuntu10.42
  qemu-utils                      1:2.5+dfsg-5ubuntu10.42

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

References:
  https://usn.ubuntu.com/4191-1
  CVE-2019-12068, CVE-2019-12155, CVE-2019-13164, CVE-2019-14378,
  CVE-2019-15890

Package Information:
  https://launchpad.net/ubuntu/+source/qemu/1:4.0+dfsg-0ubuntu9.1
  https://launchpad.net/ubuntu/+source/qemu/1:3.1+dfsg-2ubuntu3.6
  https://launchpad.net/ubuntu/+source/qemu/1:2.11+dfsg-1ubuntu7.20
  https://launchpad.net/ubuntu/+source/qemu/1:2.5+dfsg-5ubuntu10.42