USN-4069-1: Linux kernel vulnerabilities

USN-4069-1: Linux kernel vulnerabilities

linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities

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

• Ubuntu 19.04

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-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 (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

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

Ubuntu 19.04

linux-image-5.0.0-1011-aws – 5.0.0-1011.12

linux-image-5.0.0-1011-gcp – 5.0.0-1011.11

linux-image-5.0.0-1011-kvm – 5.0.0-1011.12

linux-image-5.0.0-1012-azure – 5.0.0-1012.12

linux-image-5.0.0-1013-raspi2 – 5.0.0-1013.13

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-5.0.0-21-generic-lpae – 5.0.0-21.22

linux-image-5.0.0-21-lowlatency – 5.0.0-21.22

linux-image-aws – 5.0.0.1011.11

linux-image-azure – 5.0.0.1012.11

linux-image-gcp – 5.0.0.1011.11

linux-image-generic – 5.0.0.21.22

linux-image-generic-lpae – 5.0.0.21.22

linux-image-gke – 5.0.0.1011.11

linux-image-kvm – 5.0.0.1011.11

linux-image-lowlatency – 5.0.0.21.22

linux-image-raspi2 – 5.0.0.1013.10

linux-image-snapdragon – 5.0.0.1017.10

linux-image-virtual – 5.0.0.21.22

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-2019-11487
• CVE-2019-11599
• CVE-2019-11833
• CVE-2019-11884

Source: USN-4069-1: Linux kernel vulnerabilities