==========================================================================
Ubuntu Security Notice USN-3487-1
November 21, 2017

linux, linux-raspi2 vulnerabilities
==========================================================================

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

- Ubuntu 17.10

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux: Linux kernel
- linux-raspi2: Linux kernel for Raspberry Pi 2

Details:

It was discovered that the KVM subsystem in the Linux kernel did not
properly keep track of nested levels in guest page tables. A local attacker
in a guest VM could use this to cause a denial of service (host OS crash)
or possibly execute arbitrary code in the host OS. (CVE-2017-12188)

It was discovered that on the PowerPC architecture, the kernel did not
properly sanitize the signal stack when handling sigreturn(). A local
attacker could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2017-1000255)

Bo Zhang discovered that the netlink wireless configuration interface in
the Linux kernel did not properly validate attributes when handling certain
requests. A local attacker with the CAP_NET_ADMIN could use this to cause a
denial of service (system crash). (CVE-2017-12153)

It was discovered that the nested KVM implementation in the Linux kernel in
some situations did not properly prevent second level guests from reading
and writing the hardware CR8 register. A local attacker in a guest could
use this to cause a denial of service (system crash). (CVE-2017-12154)

Vitaly Mayatskikh discovered that the SCSI subsystem in the Linux kernel
did not properly track reference counts when merging buffers. A local
attacker could use this to cause a denial of service (memory exhaustion).
(CVE-2017-12190)

It was discovered that the key management subsystem in the Linux kernel did
not properly restrict key reads on negatively instantiated keys. A local
attacker could use this to cause a denial of service (system crash).
(CVE-2017-12192)

It was discovered that the ATI Radeon framebuffer driver in the Linux
kernel did not properly initialize a data structure returned to user space.
A local attacker could use this to expose sensitive information (kernel
memory). (CVE-2017-14156)

ChunYu Wang discovered that the iSCSI transport implementation in the Linux
kernel did not properly validate data structures. A local attacker could
use this to cause a denial of service (system crash). (CVE-2017-14489)

Alexander Potapenko discovered an information leak in the waitid
implementation of the Linux kernel. A local attacker could use this to
expose sensitive information (kernel memory). (CVE-2017-14954)

It was discovered that a race condition existed in the ALSA subsystem of
the Linux kernel when creating and deleting a port via ioctl(). A local
attacker could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2017-15265)

Dmitry Vyukov discovered that the Floating Point Unit (fpu) subsystem in
the Linux kernel did not properly handle attempts to set reserved bits in a
task's extended state (xstate) area. A local attacker could use this to
cause a denial of service (system crash). (CVE-2017-15537)

It was discovered that a race condition existed in the packet fanout
implementation in the Linux kernel. A local attacker could use this to
cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2017-15649)

Andrey Konovalov discovered a use-after-free vulnerability in the USB
serial console driver in the Linux kernel. A physically proximate attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2017-16525)

Andrey Konovalov discovered that the Ultra Wide Band driver in the Linux
kernel did not properly check for an error condition. A physically
proximate attacker could use this to cause a denial of service (system
crash) or possibly execute arbitrary code. (CVE-2017-16526)

Andrey Konovalov discovered that the ALSA subsystem in the Linux kernel
contained a use-after-free vulnerability. A local attacker could use this
to cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2017-16527)

Andrey Konovalov discovered that the ALSA subsystem in the Linux kernel did
not properly validate USB audio buffer descriptors. A physically proximate
attacker could use this cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2017-16529)

Andrey Konovalov discovered that the USB unattached storage driver in the
Linux kernel contained out-of-bounds error when handling alternative
settings. A physically proximate attacker could use to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2017-16530)

Andrey Konovalov discovered that the USB subsystem in the Linux kernel did
not properly validate USB interface association descriptors. A physically
proximate attacker could use this to cause a denial of service (system
crash). (CVE-2017-16531)

Andrey Konovalov discovered that the USB subsystem in the Linux kernel did
not properly validate USB HID descriptors. A physically proximate attacker
could use this to cause a denial of service (system crash).
(CVE-2017-16533)

Andrey Konovalov discovered that the USB subsystem in the Linux kernel did
not properly validate CDC metadata. A physically proximate attacker could
use this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2017-16534)

Update instructions:

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

Ubuntu 17.10:
  linux-image-4.13.0-1006-raspi2  4.13.0-1006.6
  linux-image-4.13.0-17-generic   4.13.0-17.20
  linux-image-4.13.0-17-generic-lpae  4.13.0-17.20
  linux-image-4.13.0-17-lowlatency  4.13.0-17.20
  linux-image-generic             4.13.0.17.18
  linux-image-generic-lpae        4.13.0.17.18
  linux-image-lowlatency          4.13.0.17.18
  linux-image-raspi2              4.13.0.1006.4

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

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.

References:
  https://www.ubuntu.com/usn/usn-3487-1
  CVE-2017-1000255, CVE-2017-12153, CVE-2017-12154, CVE-2017-12188,
  CVE-2017-12190, CVE-2017-12192, CVE-2017-14156, CVE-2017-14489,
  CVE-2017-14954, CVE-2017-15265, CVE-2017-15537, CVE-2017-15649,
  CVE-2017-16525, CVE-2017-16526, CVE-2017-16527, CVE-2017-16529,
  CVE-2017-16530, CVE-2017-16531, CVE-2017-16533, CVE-2017-16534

Package Information:
  https://launchpad.net/ubuntu/+source/linux/4.13.0-17.20
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.13.0-1006.6