Ubuntu 18.04 LTS: USN-4325-1 Critical Security Updates for Kernel

ubuntu

April 7, 2020

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-gke-5.0: Linux kernel for Google Container Engine (GKE) systems

- linux-oem-osp1: Linux kernel for OEM processors- linux-oracle-5.0: Linux kernel for Oracle Cloud systems

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)

Topics Covered

security advisory denial of service system update ubuntu linux kernel

Update Instructions

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

Ubuntu 18.04 LTS:
  linux-image-5.0.0-1014-oracle   5.0.0-1014.19
  linux-image-5.0.0-1033-gke      5.0.0-1033.34
  linux-image-5.0.0-1034-gcp      5.0.0-1034.35
  linux-image-5.0.0-1036-azure    5.0.0-1036.38
  linux-image-5.0.0-1047-oem-osp1  5.0.0-1047.52
  linux-image-azure               5.0.0.1036.47
  linux-image-gcp                 5.0.0.1034.38
  linux-image-gke-5.0             5.0.0.1033.21
  linux-image-oem-osp1            5.0.0.1047.50
  linux-image-oracle              5.0.0.1014.15

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.