A Linux kernel security update has been released for Ubuntu Linux 16.04 LTS, and 14.04 ESM.

USN-4527-1: Linux kernel vulnerabilities

=========================================================================
Ubuntu Security Notice USN-4527-1
September 22, 2020

linux, linux-aws, linux-lts-xenial, linux-raspi2, linux-snapdragon
vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 LTS
- Ubuntu 14.04 ESM

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux: Linux kernel
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-raspi2: Linux kernel for Raspberry Pi (V8) systems
- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors
- linux-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty

Details:

It was discovered that the Conexant 23885 TV card device driver for the
Linux kernel did not properly deallocate memory in some error conditions. A
local attacker could use this to cause a denial of service (memory
exhaustion). (CVE-2019-19054)

It was discovered that the Atheros HTC based wireless driver in the Linux
kernel did not properly deallocate in certain error conditions. A local
attacker could use this to cause a denial of service (memory exhaustion).
(CVE-2019-19073, CVE-2019-19074)

Yue Haibing discovered that the Linux kernel did not properly handle
reference counting in sysfs for network devices in some situations. A local
attacker could possibly use this to cause a denial of service.
(CVE-2019-20811)

It was discovered that the F2FS file system in the Linux kernel did not
properly perform bounds checking in some situations, leading to an out-of-
bounds read. A local attacker could possibly use this to expose sensitive
information (kernel memory). (CVE-2019-9445)

It was discovered that the F2FS file system in the Linux kernel did not
properly validate xattr meta data in some situations, leading to an out-of-
bounds read. An attacker could use this to construct a malicious F2FS image
that, when mounted, could expose sensitive information (kernel memory).
(CVE-2019-9453)

It was discovered that the F2FS file system implementation in the Linux
kernel did not properly perform bounds checking on xattrs in some
situations. A local attacker could possibly use this to expose sensitive
information (kernel memory). (CVE-2020-0067)

It was discovered that the NFS client implementation in the Linux kernel
did not properly perform bounds checking before copying security labels in
some situations. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2020-25212)

Update instructions:

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

Ubuntu 16.04 LTS:
linux-image-4.4.0-1114-aws 4.4.0-1114.127
linux-image-4.4.0-1139-raspi2 4.4.0-1139.148
linux-image-4.4.0-1143-snapdragon 4.4.0-1143.152
linux-image-4.4.0-190-generic 4.4.0-190.220
linux-image-4.4.0-190-generic-lpae 4.4.0-190.220
linux-image-4.4.0-190-lowlatency 4.4.0-190.220
linux-image-4.4.0-190-powerpc-e500mc 4.4.0-190.220
linux-image-4.4.0-190-powerpc-smp 4.4.0-190.220
linux-image-4.4.0-190-powerpc64-emb 4.4.0-190.220
linux-image-4.4.0-190-powerpc64-smp 4.4.0-190.220
linux-image-aws 4.4.0.1114.119
linux-image-generic 4.4.0.190.196
linux-image-generic-lpae 4.4.0.190.196
linux-image-lowlatency 4.4.0.190.196
linux-image-powerpc-e500mc 4.4.0.190.196
linux-image-powerpc-smp 4.4.0.190.196
linux-image-powerpc64-emb 4.4.0.190.196
linux-image-powerpc64-smp 4.4.0.190.196
linux-image-raspi2 4.4.0.1139.139
linux-image-snapdragon 4.4.0.1143.135
linux-image-virtual 4.4.0.190.196

Ubuntu 14.04 ESM:
linux-image-4.4.0-1078-aws 4.4.0-1078.82
linux-image-4.4.0-190-generic 4.4.0-190.220~14.04.1
linux-image-4.4.0-190-generic-lpae 4.4.0-190.220~14.04.1
linux-image-4.4.0-190-lowlatency 4.4.0-190.220~14.04.1
linux-image-4.4.0-190-powerpc-e500mc 4.4.0-190.220~14.04.1
linux-image-4.4.0-190-powerpc-smp 4.4.0-190.220~14.04.1
linux-image-4.4.0-190-powerpc64-emb 4.4.0-190.220~14.04.1
linux-image-4.4.0-190-powerpc64-smp 4.4.0-190.220~14.04.1
linux-image-aws 4.4.0.1078.75
linux-image-generic-lpae-lts-xenial 4.4.0.190.166
linux-image-generic-lts-xenial 4.4.0.190.166
linux-image-lowlatency-lts-xenial 4.4.0.190.166
linux-image-powerpc-e500mc-lts-xenial 4.4.0.190.166
linux-image-powerpc-smp-lts-xenial 4.4.0.190.166
linux-image-powerpc64-emb-lts-xenial 4.4.0.190.166
linux-image-powerpc64-smp-lts-xenial 4.4.0.190.166
linux-image-virtual-lts-xenial 4.4.0.190.166

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/4527-1
CVE-2019-19054, CVE-2019-19073, CVE-2019-19074, CVE-2019-20811,
CVE-2019-9445, CVE-2019-9453, CVE-2020-0067, CVE-2020-25212

Package Information:
  https://launchpad.net/ubuntu/+source/linux/4.4.0-190.220
  https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1114.127
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1139.148
  https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1143.152