==========================================================================
Ubuntu Security Notice USN-4182-1
November 12, 2019

intel-microcode update
==========================================================================

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

- Ubuntu 19.10
- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Intel Microcode.

Software Description:
- intel-microcode: Processor microcode for Intel CPUs

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. (CVE-2019-11135)

It was discovered that certain Intel Xeon processors did not properly
restrict access to a voltage modulation interface. A local privileged
attacker could use this to cause a denial of service (system crash).
(CVE-2019-11139)

Update instructions:

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

Ubuntu 19.10:
  intel-microcode                 3.20191112-0ubuntu0.19.10.2

Ubuntu 19.04:
  intel-microcode                 3.20191112-0ubuntu0.19.04.2

Ubuntu 18.04 LTS:
  intel-microcode                 3.20191112-0ubuntu0.18.04.2

Ubuntu 16.04 LTS:
  intel-microcode                 3.20191112-0ubuntu0.16.04.2

After a standard system update you need to reboot your computer.
Please note that in order to fully mitigate CVE-2019-11139, a warm
reboot is required *after* applying the microcode update; so in effect
a second reboot.

References:
  https://usn.ubuntu.com/4182-1
  CVE-2019-11135, CVE-2019-11139,
  https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/TAA_MCEPSC_i915

Package Information:
  https://launchpad.net/ubuntu/+source/intel-microcode/3.20191112-0ubuntu0.19.10.2
  https://launchpad.net/ubuntu/+source/intel-microcode/3.20191112-0ubuntu0.19.04.2
  https://launchpad.net/ubuntu/+source/intel-microcode/3.20191112-0ubuntu0.18.04.2
  https://launchpad.net/ubuntu/+source/intel-microcode/3.20191112-0ubuntu0.16.04.2