1. Ubuntu Security Notices
  2. USN-4187-1

USN-4187-1: Linux kernel vulnerability

Publication date

13 November 2019

Overview

The system could be made to expose sensitive information.

Releases

Packages

Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo,
Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz
Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel
processors using Transactional Synchronization Extensions (TSX) could
expose memory contents previously stored in microarchitectural buffers to a
malicious process that is executing on the same CPU core. A local attacker
could use this to expose sensitive information.

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo,
Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz
Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel
processors using Transactional Synchronization Extensions (TSX) could
expose memory contents previously stored in microarchitectural buffers to a
malicious process that is executing on the same CPU core. A local attacker
could use this to expose sensitive information.

Update instructions

Please note that mitigating the TSX (CVE-2019-11135) issue requires a corresponding Intel processor microcode update. 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-server –  3.13.0.175.186
linux-image-3.13.0-175-generic –  3.13.0-175.226
linux-image-3.13.0-175-lowlatency –  3.13.0-175.226
linux-image-virtual –  3.13.0.175.186
linux-image-3.13.0-175-generic-lpae –  3.13.0-175.226
linux-image-generic –  3.13.0.175.186
linux-image-generic-lpae –  3.13.0.175.186
linux-image-lowlatency –  3.13.0.175.186

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References

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