USN-4319-1: Linux kernel vulnerabilities

10 April 2020

linux, linux-aws, linux-gcp, linux-gcp-5.3, linux-hwe, linux-kvm, linux-oracle, linux-oracle-5.3, linux-raspi2, linux-raspi2-5.3 vulnerabilities

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

  • Ubuntu 19.10
  • Ubuntu 18.04 LTS

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-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-azure-5.3 - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp-5.3 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-oracle-5.3 - Linux kernel Oracle Cloud systems
  • linux-raspi2-5.3 - Linux kernel for Raspberry Pi 2

Details

It was discovered that the IPMI message handler implementation in the Linux kernel did not properly deallocate memory in certain situations. A local attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-19046)

Al Viro discovered that the vfs layer in the Linux kernel contained a use- after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-8428)

Update instructions

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

Ubuntu 19.10
linux-image-5.3.0-1014-oracle - 5.3.0-1014.15
linux-image-5.3.0-1015-kvm - 5.3.0-1015.16
linux-image-5.3.0-1016-aws - 5.3.0-1016.17
linux-image-5.3.0-1017-gcp - 5.3.0-1017.18
linux-image-5.3.0-1019-azure - 5.3.0-1019.20
linux-image-5.3.0-1022-raspi2 - 5.3.0-1022.24
linux-image-5.3.0-46-generic - 5.3.0-46.38
linux-image-5.3.0-46-generic-lpae - 5.3.0-46.38
linux-image-5.3.0-46-lowlatency - 5.3.0-46.38
linux-image-5.3.0-46-snapdragon - 5.3.0-46.38
linux-image-aws - 5.3.0.1016.18
linux-image-azure - 5.3.0.1019.38
linux-image-gcp - 5.3.0.1017.18
linux-image-generic - 5.3.0.46.39
linux-image-generic-lpae - 5.3.0.46.39
linux-image-gke - 5.3.0.1017.18
linux-image-kvm - 5.3.0.1015.17
linux-image-lowlatency - 5.3.0.46.39
linux-image-oracle - 5.3.0.1014.15
linux-image-raspi2 - 5.3.0.1022.19
linux-image-snapdragon - 5.3.0.46.39
linux-image-virtual - 5.3.0.46.39
Ubuntu 18.04 LTS
linux-image-5.3.0-1014-oracle - 5.3.0-1014.15~18.04.1
linux-image-5.3.0-1017-gcp - 5.3.0-1017.18~18.04.1
linux-image-5.3.0-1019-azure - 5.3.0-1019.20~18.04.1
linux-image-5.3.0-1022-raspi2 - 5.3.0-1022.24~18.04.1
linux-image-5.3.0-46-generic - 5.3.0-46.38~18.04.1
linux-image-5.3.0-46-generic-lpae - 5.3.0-46.38~18.04.1
linux-image-5.3.0-46-lowlatency - 5.3.0-46.38~18.04.1
linux-image-azure-edge - 5.3.0.1019.19
linux-image-gcp-edge - 5.3.0.1017.16
linux-image-generic-hwe-18.04 - 5.3.0.46.102
linux-image-generic-lpae-hwe-18.04 - 5.3.0.46.102
linux-image-lowlatency-hwe-18.04 - 5.3.0.46.102
linux-image-oracle-edge - 5.3.0.1014.13
linux-image-raspi2-hwe-18.04 - 5.3.0.1022.11
linux-image-snapdragon-hwe-18.04 - 5.3.0.46.102
linux-image-virtual-hwe-18.04 - 5.3.0.46.102

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

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