USN-4188-1: Linux kernel vulnerability

13 November 2019

linux, linux-lts-trusty vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 12.04 ESM

Summary

The system could be made to expose sensitive information.

Software Description

  • linux - Linux kernel
  • linux-lts-trusty - Linux hardware enablement kernel from Trusty for Precise ESM

Details

Stephan van Schaik, Alyssa Milburn, Sebastian Ă–sterlund, 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

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

Ubuntu 12.04 ESM
linux-image-3.13.0-175-generic - 3.13.0-175.226~12.04.1
linux-image-3.13.0-175-generic-lpae - 3.13.0-175.226~12.04.1
linux-image-3.13.0-175-lowlatency - 3.13.0-175.226~12.04.1
linux-image-3.2.0-144-generic - 3.2.0-144.191
linux-image-3.2.0-144-generic-pae - 3.2.0-144.191
linux-image-3.2.0-144-virtual - 3.2.0-144.191
linux-image-generic - 3.2.0.144.159
linux-image-generic-lpae-lts-trusty - 3.13.0.175.163
linux-image-generic-lts-trusty - 3.13.0.175.163
linux-image-generic-pae - 3.2.0.144.159
linux-image-server - 3.2.0.144.159
linux-image-virtual - 3.2.0.144.159

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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.

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