USN-4412-1: Linux kernel vulnerabilities

6 July 2020

Several security issues were fixed in the Linux kernel.

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Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-aws-5.3 - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-azure-5.3 - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gcp-5.3 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gke-5.3 - Linux kernel for Google Container Engine (GKE) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-kvm - Linux kernel for cloud environments
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-oracle-5.3 - Linux kernel for Oracle Cloud systems
  • linux-raspi2-5.3 - Linux kernel for Raspberry Pi (V7) systems

Details

Matthew Sheets discovered that the SELinux network label handling
implementation in the Linux kernel could be coerced into de-referencing a
NULL pointer. A remote attacker could use this to cause a denial of service
(system crash). (CVE-2020-10711)

It was discovered that the SCSI generic (sg) driver in the Linux kernel did
not properly handle certain error conditions correctly. A local privileged
attacker could use this to cause a denial of service (system crash).
(CVE-2020-12770)

It was discovered that the USB Gadget device driver in the Linux kernel did
not validate arguments passed from configfs in some situations. A local
attacker could possibly use this to cause a denial of service (system
crash) or possibly expose sensitive information. (CVE-2020-13143)

Dmitry Vyukov discovered that the SELinux netlink security hook in the
Linux kernel did not validate messages in some situations. A privileged
attacker could use this to bypass SELinux netlink restrictions.
(CVE-2020-10751)

It was discovered that the KVM implementation in the Linux kernel did not
properly deallocate memory on initialization for some processors. A local
attacker could possibly use this to cause a denial of service.
(CVE-2020-12768)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 19.10
Ubuntu 18.04

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.