Ubuntu 16.04 LTS: USN-3981-2 Moderate: Linux Kernel Memory Exposure

ubuntu

May 15, 2019

Several security issues were fixed in the Linux kernel.

Summary

Several security issues were fixed in the Linux kernel.

Software Description:

- linux-azure: Linux kernel for Microsoft Azure Cloud systems

- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems

- linux-hwe: Linux hardware enablement (HWE) kernel

- linux-oracle: Linux kernel for Oracle Cloud systems

Details:

USN-3981-1 fixed vulnerabilities in the Linux kernel for Ubuntu 18.04

LTS. This update provides the corresponding updates for the Linux

Hardware Enablement (HWE) kernel from Ubuntu 18.04 LTS for Ubuntu

16.04 LTS and for the Linux Azure kernel for Ubuntu 14.04 LTS.

Ke Sun, Henrique Kawakami, Kekai Hu, Rodrigo Branco, Giorgi Maisuradze, Dan

Horea Lutas, Andrei Lutas, Volodymyr Pikhur, Stephan van Schaik, Alyssa

Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos,

Cristiano Giuffrida, Moritz Lipp, Michael Schwarz, and Daniel Gruss

discovered that memory previously stored in microarchitectural fill buffers

of an Intel CPU core ...

Read the Full Advisory

Topics Covered

security advisory denial of service ubuntu linux kernel memory exposure cloud linux hardware

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.15.0-1013-oracle  4.15.0-1013.15~16.04.1
  linux-image-4.15.0-1032-gcp     4.15.0-1032.34~16.04.1
  linux-image-4.15.0-1045-azure   4.15.0-1045.49
  linux-image-4.15.0-50-generic   4.15.0-50.54~16.04.1
  linux-image-4.15.0-50-generic-lpae  4.15.0-50.54~16.04.1
  linux-image-4.15.0-50-lowlatency  4.15.0-50.54~16.04.1
  linux-image-azure               4.15.0.1045.49
  linux-image-gcp                 4.15.0.1032.46
  linux-image-generic-hwe-16.04   4.15.0.50.71
  linux-image-generic-lpae-hwe-16.04  4.15.0.50.71
  linux-image-gke                 4.15.0.1032.46
  linux-image-lowlatency-hwe-16.04  4.15.0.50.71
  linux-image-oem                 4.15.0.50.71
  linux-image-oracle              4.15.0.1013.7
  linux-image-virtual-hwe-16.04   4.15.0.50.71

Ubuntu 14.04 ESM:
  linux-image-4.15.0-1045-azure   4.15.0-1045.49~14.04.1
  linux-image-azure               4.15.0.1045.32

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

Please note that fully mitigating the Microarchitectural Data Sampling
(MDS) issues (CVE-2018-12126, CVE-2018-12127, CVE-2018-12130, and
CVE-2019-11091) requires corresponding processor microcode/firmware
updates or, in virtual environments, hypervisor updates.