The following updates has been released for Ubuntu Linux:

USN-3575-1: QEMU vulnerabilities
USN-3576-1: libvirt vulnerabilities
USN-3577-1: CUPS vulnerability

USN-3575-1: QEMU vulnerabilities

==========================================================================
Ubuntu Security Notice USN-3575-1
February 20, 2018

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

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

- Ubuntu 17.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in QEMU.

Software Description:
- qemu: Machine emulator and virtualizer

Details:

It was discovered that QEMU incorrectly handled guest ram. A privileged
attacker inside the guest could use this issue to cause QEMU to crash,
resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS
and Ubuntu 16.04 LTS. (CVE-2017-11334)

David Buchanan discovered that QEMU incorrectly handled the VGA device. A
privileged attacker inside the guest could use this issue to cause QEMU to
crash, resulting in a denial of service. This issue was only addressed in
Ubuntu 17.10. (CVE-2017-13672)

Thomas Garnier discovered that QEMU incorrectly handled multiboot. An
attacker could use this issue to cause QEMU to crash, resulting in a denial
of service, or possibly execute arbitrary code on the host. In the default
installation, when QEMU is used with libvirt, attackers would be isolated
by the libvirt AppArmor profile. This issue only affected Ubuntu 14.04 LTS
and Ubuntu 16.04 LTS. (CVE-2017-14167)

Tuomas Tynkkynen discovered that QEMU incorrectly handled VirtFS directory
sharing. An attacker could use this issue to obtain sensitive information
from host memory. (CVE-2017-15038)

Eric Blake discovered that QEMU incorrectly handled memory in the
NBD server. An attacker could use this issue to cause the NBD server to
crash, resulting in a denial of service. This issue only affected Ubuntu
17.10. (CVE-2017-15118)

Eric Blake discovered that QEMU incorrectly handled certain options to the
NBD server. An attacker could use this issue to cause the NBD server to
crash, resulting in a denial of service. This issue only affected Ubuntu
14.04 LTS and Ubuntu 16.04 LTS. (CVE-2017-15119)

Daniel Berrange discovered that QEMU incorrectly handled the VNC server. A
remote attacker could possibly use this issue to consume memory, resulting
in a denial of service. This issue was only addressed in Ubuntu 17.10.
(CVE-2017-15124)

Carl Brassey discovered that QEMU incorrectly handled certain websockets. A
remote attacker could possibly use this issue to consume memory, resulting
in a denial of service. This issue only affected Ubuntu 17.10.
(CVE-2017-15268)

Guoxiang Niu discovered that QEMU incorrectly handled the Cirrus VGA
device. A privileged attacker inside the guest could use this issue to
cause QEMU to crash, resulting in a denial of service. (CVE-2017-15289)

Cyrille Chatras discovered that QEMU incorrectly handled certain PS2 values
during migration. An attacker could possibly use this issue to cause QEMU
to crash, resulting in a denial of service, or possibly execute arbitrary
code. This issue only affected Ubuntu 16.04 LTS and Ubuntu 17.10.
(CVE-2017-16845)

It was discovered that QEMU incorrectly handled the Virtio Vring
implementation. An attacker could possibly use this issue to cause QEMU to
crash, resulting in a denial of service. This issue only affected Ubuntu
16.04 LTS and Ubuntu 17.10. (CVE-2017-17381)

Eric Blake discovered that QEMU incorrectly handled certain rounding
operations. An attacker could possibly use this issue to cause QEMU to
crash, resulting in a denial of service. This issue only affected Ubuntu
14.04 LTS and Ubuntu 16.04 LTS. (CVE-2017-18043)

Jiang Xin and Lin ZheCheng discovered that QEMU incorrectly handled the
VGA device. A privileged attacker inside the guest could use this issue to
cause QEMU to crash, resulting in a denial of service. (CVE-2018-5683)

Update instructions:

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

Ubuntu 17.10:
qemu-system 1:2.10+dfsg-0ubuntu3.5
qemu-system-aarch64 1:2.10+dfsg-0ubuntu3.5
qemu-system-arm 1:2.10+dfsg-0ubuntu3.5
qemu-system-mips 1:2.10+dfsg-0ubuntu3.5
qemu-system-misc 1:2.10+dfsg-0ubuntu3.5
qemu-system-ppc 1:2.10+dfsg-0ubuntu3.5
qemu-system-s390x 1:2.10+dfsg-0ubuntu3.5
qemu-system-sparc 1:2.10+dfsg-0ubuntu3.5
qemu-system-x86 1:2.10+dfsg-0ubuntu3.5

Ubuntu 16.04 LTS:
qemu-system 1:2.5+dfsg-5ubuntu10.22
qemu-system-aarch64 1:2.5+dfsg-5ubuntu10.22
qemu-system-arm 1:2.5+dfsg-5ubuntu10.22
qemu-system-mips 1:2.5+dfsg-5ubuntu10.22
qemu-system-misc 1:2.5+dfsg-5ubuntu10.22
qemu-system-ppc 1:2.5+dfsg-5ubuntu10.22
qemu-system-s390x 1:2.5+dfsg-5ubuntu10.22
qemu-system-sparc 1:2.5+dfsg-5ubuntu10.22
qemu-system-x86 1:2.5+dfsg-5ubuntu10.22

Ubuntu 14.04 LTS:
qemu-system 2.0.0+dfsg-2ubuntu1.39
qemu-system-aarch64 2.0.0+dfsg-2ubuntu1.39
qemu-system-arm 2.0.0+dfsg-2ubuntu1.39
qemu-system-mips 2.0.0+dfsg-2ubuntu1.39
qemu-system-misc 2.0.0+dfsg-2ubuntu1.39
qemu-system-ppc 2.0.0+dfsg-2ubuntu1.39
qemu-system-sparc 2.0.0+dfsg-2ubuntu1.39
qemu-system-x86 2.0.0+dfsg-2ubuntu1.39

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

References:
https://www.ubuntu.com/usn/usn-3575-1
CVE-2017-11334, CVE-2017-13672, CVE-2017-14167, CVE-2017-15038,
CVE-2017-15118, CVE-2017-15119, CVE-2017-15124, CVE-2017-15268,
CVE-2017-15289, CVE-2017-16845, CVE-2017-17381, CVE-2017-18043,
CVE-2018-5683

Package Information:
https://launchpad.net/ubuntu/+source/qemu/1:2.10+dfsg-0ubuntu3.5
https://launchpad.net/ubuntu/+source/qemu/1:2.5+dfsg-5ubuntu10.22
https://launchpad.net/ubuntu/+source/qemu/2.0.0+dfsg-2ubuntu1.39

USN-3576-1: libvirt vulnerabilities

==========================================================================
Ubuntu Security Notice USN-3576-1
February 20, 2018

libvirt vulnerabilities
==========================================================================

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

- Ubuntu 17.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in libvirt.

Software Description:
- libvirt: Libvirt virtualization toolkit

Details:

Vivian Zhang and Christoph Anton Mitterer discovered that libvirt
incorrectly disabled password authentication when the VNC password was set
to an empty string. A remote attacker could possibly use this issue to
bypass authentication, contrary to expectations. This issue only affected
Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-5008)

Daniel P. Berrange discovered that libvirt incorrectly handled validating
SSL/TLS certificates. A remote attacker could possibly use this issue to
obtain sensitive information. This issue only affected Ubuntu 17.10.
(CVE-2017-1000256)

Daniel P. Berrange and Peter Krempa discovered that libvirt incorrectly
handled large QEMU replies. An attacker could possibly use this issue to
cause libvirt to crash, resulting in a denial of service. (CVE-2018-5748)

Pedro Sampaio discovered that libvirt incorrectly handled the libnss_dns.so
module. An attacker in a libvirt_lxc session could possibly use this issue
to execute arbitrary code. This issue only affected Ubuntu 16.04 LTS and
Ubuntu 17.10. (CVE-2018-6764)

Update instructions:

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

Ubuntu 17.10:
libvirt-bin 3.6.0-1ubuntu6.3
libvirt0 3.6.0-1ubuntu6.3

Ubuntu 16.04 LTS:
libvirt-bin 1.3.1-1ubuntu10.19
libvirt0 1.3.1-1ubuntu10.19

Ubuntu 14.04 LTS:
libvirt-bin 1.2.2-0ubuntu13.1.26
libvirt0 1.2.2-0ubuntu13.1.26

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
https://www.ubuntu.com/usn/usn-3576-1
CVE-2016-5008, CVE-2017-1000256, CVE-2018-5748, CVE-2018-6764

Package Information:
https://launchpad.net/ubuntu/+source/libvirt/3.6.0-1ubuntu6.3
https://launchpad.net/ubuntu/+source/libvirt/1.3.1-1ubuntu10.19
https://launchpad.net/ubuntu/+source/libvirt/1.2.2-0ubuntu13.1.26

USN-3577-1: CUPS vulnerability

==========================================================================
Ubuntu Security Notice USN-3577-1
February 21, 2018

cups vulnerability
==========================================================================

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

- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

CUPS could be made to provide access to printers over the network.

Software Description:
- cups: Common UNIX Printing System(tm)

Details:

Jann Horn discovered that CUPS permitted HTTP requests with the Host
header set to "localhost.localdomain" from the loopback interface. If a
user were tricked in to opening a specially crafted website in their web
browser, an attacker could potentially exploit this to obtain sensitive
information or control printers, via a DNS rebinding attack.
(CVE-2017-18190)

Update instructions:

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

Ubuntu 16.04 LTS:
cups 2.1.3-4ubuntu0.4

Ubuntu 14.04 LTS:
cups 1.7.2-0ubuntu1.9

In general, a standard system update will make all the necessary changes.

References:
https://www.ubuntu.com/usn/usn-3577-1
CVE-2017-18190

Package Information:
https://launchpad.net/ubuntu/+source/cups/2.1.3-4ubuntu0.4
https://launchpad.net/ubuntu/+source/cups/1.7.2-0ubuntu1.9