1. Ubuntu Security Notices
  2. USN-4017-2

USN-4017-2: Linux kernel vulnerabilities

Publication date

17 June 2019

Overview

The system could be made to crash if it received specially crafted network traffic.

Releases

Packages

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

Details

USN-4017-1 fixed vulnerabilities in the Linux kernel for Ubuntu.
This update provides the corresponding updates for the Linux kernel
for Ubuntu 16.04 ESM and Ubuntu 14.04 ESM.

Jonathan Looney discovered that the TCP retransmission queue implementation
in the Linux kernel could be fragmented when handling certain TCP Selective
Acknowledgment (SACK) sequences. A remote attacker could use this to cause
a denial of service. (CVE-2019-11478)

Jonathan Looney discovered that an integer overflow existed in the Linux
kernel when handling TCP Selective Acknowledgments (SACKs). A remote
attacker could use this to cause a denial of service (system crash).
(CVE-2019-11477)

USN-4017-1 fixed vulnerabilities in the Linux kernel for Ubuntu.
This update provides the corresponding updates for the Linux kernel
for Ubuntu 16.04 ESM and Ubuntu 14.04 ESM.

Jonathan Looney discovered that the TCP retransmission queue implementation
in the Linux kernel could be fragmented when handling certain TCP Selective
Acknowledgment (SACK) sequences. A remote attacker could use this to cause
a denial of service. (CVE-2019-11478)

Jonathan Looney discovered that an integer overflow existed in the Linux
kernel when handling TCP Selective Acknowledgments (SACKs). A remote
attacker could use this to cause a denial of service (system crash).
(CVE-2019-11477)

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-4.4.0-151-generic-lpae –  4.4.0-151.178~14.04.1
linux-image-4.4.0-1046-aws –  4.4.0-1046.50
linux-image-generic-lpae-lts-xenial –  4.4.0.151.133
linux-image-generic-lts-xenial –  4.4.0.151.133
linux-image-3.13.0-171-generic-lpae –  3.13.0-171.222
linux-image-3.13.0-171-lowlatency –  3.13.0-171.222
linux-image-azure –  4.15.0.1047.34
linux-image-4.4.0-151-lowlatency –  4.4.0-151.178~14.04.1
linux-image-4.15.0-1047-azure –  4.15.0-1047.51~14.04.1
linux-image-generic –  3.13.0.171.182
linux-image-4.4.0-151-generic –  4.4.0-151.178~14.04.1
linux-image-aws –  4.4.0.1046.47
linux-image-lowlatency-lts-xenial –  4.4.0.151.133
linux-image-3.13.0-171-generic –  3.13.0-171.222
linux-image-generic-lpae –  3.13.0.171.182
12.04 precise linux-image-generic-lpae-lts-trusty –  3.13.0.171.159
linux-image-generic-lts-trusty –  3.13.0.171.159
linux-image-generic –  3.2.0.141.156
linux-image-3.13.0-171-generic –  3.13.0-171.222~12.04.1
linux-image-3.2.0-141-generic –  3.2.0-141.188
linux-image-3.13.0-171-lowlatency –  3.13.0-171.222~12.04.1
linux-image-3.13.0-171-generic-lpae –  3.13.0-171.222~12.04.1

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References

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