1. Ubuntu Security Notices
  2. USN-4041-2

USN-4041-2: Linux kernel (HWE) update

Publication date

29 June 2019

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

USN-4041-1 provided updates for the Linux kernel in Ubuntu.
This update provides the corresponding updates for the Linux kernel
for Ubuntu 16.04 ESM.

USN-4017-2 fixed vulnerabilities in the Linux kernel. Unfortunately,
the update introduced a regression that interfered with networking
applications that setup very low SO_SNDBUF values. This update fixes
the problem.

We apologize for the inconvenience.

Jonathan Looney discovered that the Linux kernel could be coerced into
segmenting responses into multiple TCP segments. A remote attacker could
construct an ongoing sequence of requests to cause a denial of service.
(CVE-2019-11479)

USN-4041-1 provided updates for the Linux kernel in Ubuntu.
This update provides the corresponding updates for the Linux kernel
for Ubuntu 16.04 ESM.

USN-4017-2 fixed vulnerabilities in the Linux kernel. Unfortunately,
the update introduced a regression that interfered with networking
applications that setup very low SO_SNDBUF values. This update fixes
the problem.

We apologize for the inconvenience.

Jonathan Looney discovered that the Linux kernel could be coerced into
segmenting responses into multiple TCP segments. A remote attacker could
construct an ongoing sequence of requests to cause a denial of service.
(CVE-2019-11479)

Update instructions

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

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
14.04 trusty linux-image-powerpc-smp-lts-xenial –  4.4.0.154.135
linux-image-generic-lpae-lts-xenial –  4.4.0.154.135
linux-image-generic-lts-xenial –  4.4.0.154.135
linux-image-4.4.0-154-powerpc64-smp –  4.4.0-154.181~14.04.1
linux-image-4.4.0-154-generic-lpae –  4.4.0-154.181~14.04.1
linux-image-4.4.0-1048-aws –  4.4.0-1048.52
linux-image-powerpc64-emb-lts-xenial –  4.4.0.154.135
linux-image-4.4.0-154-generic –  4.4.0-154.181~14.04.1
linux-image-lowlatency-lts-xenial –  4.4.0.154.135
linux-image-4.4.0-154-powerpc-smp –  4.4.0-154.181~14.04.1
linux-image-4.4.0-154-powerpc-e500mc –  4.4.0-154.181~14.04.1
linux-image-azure –  4.15.0.1049.36
linux-image-4.4.0-154-lowlatency –  4.4.0-154.181~14.04.1
linux-image-aws –  4.4.0.1048.49
linux-image-powerpc64-smp-lts-xenial –  4.4.0.154.135
linux-image-4.4.0-154-powerpc64-emb –  4.4.0-154.181~14.04.1
linux-image-powerpc-e500mc-lts-xenial –  4.4.0.154.135
linux-image-virtual-lts-xenial –  4.4.0.154.135
linux-image-4.15.0-1049-azure –  4.15.0-1049.54~14.04.1

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References

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