LSN-0066-1: Kernel Live Patch Security Notice

1 May 2020

Linux kernel vulnerabilities

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

  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 ESM

Summary

Several security issues were fixed in the Linux kernel.

Software Description

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-oem - Linux kernel for OEM processors

Details

It was discovered that the virtual terminal implementation in the Linux kernel did not properly handle resize events. A local attacker could use this to expose sensitive information. (CVE-2020-8647)

It was discovered that the virtual terminal implementation in the Linux kernel contained a race condition. A local attacker could possibly use this to cause a denial of service (system crash) or expose sensitive information. (CVE-2020-8648)

It was discovered that the virtual terminal implementation in the Linux kernel did not properly handle resize events. A local attacker could use this to expose sensitive information. (CVE-2020-8649)

Update instructions

The problem can be corrected by updating your kernel livepatch to the following versions:

Ubuntu 18.04 LTS
aws - 66.1
generic - 66.1
lowlatency - 66.1
oem - 66.1
Ubuntu 16.04 LTS
aws - 66.1
azure - 66.1
generic - 66.1
lowlatency - 66.1
Ubuntu 14.04 ESM
generic - 66.1
lowlatency - 66.1

Support Information

Kernels older than the levels listed below do not receive livepatch updates. If you are running a kernel version earlier than the one listed below, please upgrade your kernel as soon as possible.

Ubuntu 18.04 LTS
linux - 4.15.0-69
linux-aws - 4.15.0-1054
linux-azure - 5.0.0-1025
linux-gcp - 5.0.0-1025
linux-oem - 4.15.0-1063
Ubuntu 16.04 LTS
linux - 4.4.0-168
linux-aws - 4.4.0-1098
linux-azure - 4.15.0-1063
linux-hwe - 4.15.0-69
Ubuntu 14.04 ESM
linux-lts-xenial - 4.4.0-168

References