1. Ubuntu Security Notices
  2. USN-4069-1

USN-4069-1: Linux kernel vulnerabilities

Publication date

23 July 2019

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • 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-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

It was discovered that an integer overflow existed in the Linux kernel when
reference counting pages, leading to potential use-after-free issues. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code. (CVE-2019-11487)

Jann Horn discovered that a race condition existed in the Linux kernel when
performing core dumps. A local attacker could use this to cause a denial of
service (system crash) or expose sensitive information. (CVE-2019-11599)

It was discovered that the ext4 file system implementation in the Linux
kernel did not properly zero out memory in some situations. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2019-11833)

It was discovered that the Bluetooth Human Interface Device Protocol...

It was discovered that an integer overflow existed in the Linux kernel when
reference counting pages, leading to potential use-after-free issues. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code. (CVE-2019-11487)

Jann Horn discovered that a race condition existed in the Linux kernel when
performing core dumps. A local attacker could use this to cause a denial of
service (system crash) or expose sensitive information. (CVE-2019-11599)

It was discovered that the ext4 file system implementation in the Linux
kernel did not properly zero out memory in some situations. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2019-11833)

It was discovered that the Bluetooth Human Interface Device Protocol (HIDP)
implementation in the Linux kernel did not properly verify strings were
NULL terminated in certain situations. A local attacker could use this to
expose sensitive information (kernel memory). (CVE-2019-11884)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
19.04 disco linux-image-gke –  5.0.0.1011.11
linux-image-5.0.0-1017-snapdragon –  5.0.0-1017.18
linux-image-5.0.0-21-generic –  5.0.0-21.22
linux-image-5.0.0-1013-raspi2 –  5.0.0-1013.13
linux-image-gcp –  5.0.0.1011.11
linux-image-5.0.0-1012-azure –  5.0.0-1012.12
linux-image-azure –  5.0.0.1012.11
linux-image-5.0.0-21-generic-lpae –  5.0.0-21.22
linux-image-generic –  5.0.0.21.22
linux-image-virtual –  5.0.0.21.22
linux-image-5.0.0-21-lowlatency –  5.0.0-21.22
linux-image-raspi2 –  5.0.0.1013.10
linux-image-aws –  5.0.0.1011.11
linux-image-generic-lpae –  5.0.0.21.22
linux-image-snapdragon –  5.0.0.1017.10
linux-image-5.0.0-1011-kvm –  5.0.0-1011.12
linux-image-kvm –  5.0.0.1011.11
linux-image-5.0.0-1011-gcp –  5.0.0-1011.11
linux-image-lowlatency –  5.0.0.21.22
linux-image-5.0.0-1011-aws –  5.0.0-1011.12

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.

Get Ubuntu Pro

References

Have additional questions?

Talk to a member of the team ›