1. Ubuntu Security Notices
  2. USN-3444-1

USN-3444-1: Linux kernel vulnerabilities

Publication date

10 October 2017

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-gke - Linux kernel for Google Container Engine (GKE) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

Jan H. Schönherr discovered that the Xen subsystem did not properly handle
block IO merges correctly in some situations. An attacker in a guest vm
could use this to cause a denial of service (host crash) or possibly gain
administrative privileges in the host. (CVE-2017-12134)

Andrey Konovalov discovered that a divide-by-zero error existed in the TCP
stack implementation in the Linux kernel. A local attacker could use this
to cause a denial of service (system crash). (CVE-2017-14106)

Otto Ebeling discovered that the memory manager in the Linux kernel did not
properly check the effective UID in some situations. A local attacker could
use this to expose sensitive information. (CVE-2017-14140)

Jan H. Schönherr discovered that the Xen subsystem did not properly handle
block IO merges correctly in some situations. An attacker in a guest vm
could use this to cause a denial of service (host crash) or possibly gain
administrative privileges in the host. (CVE-2017-12134)

Andrey Konovalov discovered that a divide-by-zero error existed in the TCP
stack implementation in the Linux kernel. A local attacker could use this
to cause a denial of service (system crash). (CVE-2017-14106)

Otto Ebeling discovered that the memory manager in the Linux kernel did not
properly check the effective UID in some situations. A local attacker could
use this to expose sensitive information. (CVE-2017-14140)

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
16.04 xenial linux-image-4.4.0-1008-kvm –  4.4.0-1008.13
linux-image-4.4.0-1032-gke –  4.4.0-1032.32
linux-image-4.4.0-1038-aws –  4.4.0-1038.47
linux-image-4.4.0-1075-raspi2 –  4.4.0-1075.83
linux-image-4.4.0-1077-snapdragon –  4.4.0-1077.82
linux-image-4.4.0-97-generic –  4.4.0-97.120
linux-image-4.4.0-97-generic-lpae –  4.4.0-97.120
linux-image-4.4.0-97-lowlatency –  4.4.0-97.120
linux-image-4.4.0-97-powerpc-e500mc –  4.4.0-97.120
linux-image-4.4.0-97-powerpc-smp –  4.4.0-97.120
linux-image-4.4.0-97-powerpc64-emb –  4.4.0-97.120
linux-image-4.4.0-97-powerpc64-smp –  4.4.0-97.120

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References

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