=========================================================================
Ubuntu Security Notice USN-4162-2
October 23, 2019

linux-azure vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 14.04 ESM

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-azure: Linux kernel for Microsoft Azure Cloud systems

Details:

USN-4162-1 fixed vulnerabilities in the Linux kernel for Ubuntu 18.04
LTS. This update provides the corresponding updates for the Linux
kernel for Microsoft Azure Cloud systems for Ubuntu 14.04 ESM.

It was discovered that the RSI 91x Wi-Fi driver in the Linux kernel did not
did not handle detach operations correctly, leading to a use-after-free
vulnerability. A physically proximate attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2018-21008)

Wen Huang discovered that the Marvell Wi-Fi device driver in the Linux
kernel did not properly perform bounds checking, leading to a heap
overflow. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2019-14814,
CVE-2019-14815, CVE-2019-14816)

Matt Delco discovered that the KVM hypervisor implementation in the Linux
kernel did not properly perform bounds checking when handling coalesced
MMIO write operations. A local attacker with write access to /dev/kvm could
use this to cause a denial of service (system crash). (CVE-2019-14821)

Hui Peng and Mathias Payer discovered that the USB audio driver for the
Linux kernel did not properly validate device meta data. A physically
proximate attacker could use this to cause a denial of service (system
crash). (CVE-2019-15117)

Hui Peng and Mathias Payer discovered that the USB audio driver for the
Linux kernel improperly performed recursion while handling device meta
data. A physically proximate attacker could use this to cause a denial of
service (system crash). (CVE-2019-15118)

It was discovered that the Technisat DVB-S/S2 USB device driver in the
Linux kernel contained a buffer overread. A physically proximate attacker
could use this to cause a denial of service (system crash) or possibly
expose sensitive information. (CVE-2019-15505)

Brad Spengler discovered that a Spectre mitigation was improperly
implemented in the ptrace susbsystem of the Linux kernel. A local attacker
could possibly use this to expose sensitive information. (CVE-2019-15902)

It was discovered that the SMB networking file system implementation in the
Linux kernel contained a buffer overread. An attacker could use this to
expose sensitive information (kernel memory). (CVE-2019-15918)

Update instructions:

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

Ubuntu 14.04 ESM:
  linux-image-4.15.0-1061-azure   4.15.0-1061.66~14.04.1
  linux-image-azure               4.15.0.1061.47

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://usn.ubuntu.com/4162-2
  https://usn.ubuntu.com/4162-1
  CVE-2018-21008, CVE-2019-14814, CVE-2019-14815, CVE-2019-14816,
  CVE-2019-14821, CVE-2019-15117, CVE-2019-15118, CVE-2019-15505,
  CVE-2019-15902, CVE-2019-15918