Ubuntu 20.04 LTS: USN-4385-2 Moderate: Intel Microcode Regression

ubuntu

June 10, 2020

USN-4385-1 introduced a regression in the Intel Microcode for some processors.

Summary

USN-4385-1 introduced a regression in the Intel Microcode for some processors.

Software Description:

- intel-microcode: Processor microcode for Intel CPUs

Details:

USN-4385-1 provided updated Intel Processor Microcode. Unfortunately,

that update prevented certain processors in the Intel Skylake family

(06_4EH) from booting successfully. Additonally, on Ubuntu 20.04

LTS, late loading of microcode was enabled, which could lead to

system instability. This update reverts the microcode update for

the Skylake processor family and disables the late loading option on

Ubuntu 20.04 LTS.

Please note that the 'dis_ucode_ldr' kernel command line option can be

added in the boot menu to disable microcode loading for system recovery.

We apologize for the inconvenience.

Original advisory details:

It was discovered that memory contents previously stored in

microarchitectural special registers after RDRAND, RDSEED, and SGX EGETKEY

read operations on Intel client and Xeon E3 processors may b...

Read the Full Advisory

Topics Covered

security advisory security issue Ubuntu update instructions system instability regression intel microcode

Update Instructions

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

Ubuntu 20.04 LTS:
  intel-microcode                 3.20200609.0ubuntu0.20.04.2

Ubuntu 19.10:
  intel-microcode                 3.20200609.0ubuntu0.19.10.2

Ubuntu 18.04 LTS:
  intel-microcode                 3.20200609.0ubuntu0.18.04.1

Ubuntu 16.04 LTS:
  intel-microcode                 3.20200609.0ubuntu0.16.04.1

Ubuntu 14.04 ESM:
  intel-microcode                 3.20200609.0ubuntu0.14.04.1

After a standard system update you need to reboot your computer to
make all the necessary changes.