USN-4325-1: Linux kernel vulnerabilities

USN-4325-1: Linux kernel vulnerabilities

linux-azure, linux-gcp, linux-gke-5.0, linux-oem-osp1, linux-oracle-5.0 vulnerabilities

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

• Ubuntu 18.04 LTS

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)

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

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

• CVE-2019-19046
• CVE-2020-8428

Source: USN-4325-1: Linux kernel vulnerabilities