USN-4659-1: Linux kernel vulnerabilities

Publication date

2 December 2020

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-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi - Linux kernel for Raspberry Pi (V8) systems

Details

It was discovered that a race condition existed in the binder IPC
implementation in the Linux kernel, leading to a use-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2020-0423)

Daniele Antonioli, Nils Ole Tippenhauer, and Kasper Rasmussen discovered
that legacy pairing and secure-connections pairing authentication in the
Bluetooth protocol could allow an unauthenticated user to complete
authentication without pairing credentials via adjacent access. A
physically proximate attacker could use this to impersonate a previously
paired Bluetooth device. (CVE-2020-10135)

It was discovered that a race condition existed in the perf subsystem of
the Linux kernel, leading to a use-after-free vulnerability. An attacker
with access to the perf subsystem could use this...

It was discovered that a race condition existed in the binder IPC
implementation in the Linux kernel, leading to a use-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2020-0423)

Daniele Antonioli, Nils Ole Tippenhauer, and Kasper Rasmussen discovered
that legacy pairing and secure-connections pairing authentication in the
Bluetooth protocol could allow an unauthenticated user to complete
authentication without pairing credentials via adjacent access. A
physically proximate attacker could use this to impersonate a previously
paired Bluetooth device. (CVE-2020-10135)

It was discovered that a race condition existed in the perf subsystem of
the Linux kernel, leading to a use-after-free vulnerability. An attacker
with access to the perf subsystem could use this to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2020-14351)

Keyu Man discovered that the ICMP global rate limiter in the Linux kernel
could be used to assist in scanning open UDP ports. A remote attacker could
use to facilitate attacks on UDP based services that depend on source port
randomization. (CVE-2020-25705)

It was discovered that the KVM hypervisor in the Linux kernel did not
properly handle interrupts in certain situations. A local attacker in a
guest VM could possibly use this to cause a denial of service (host system
crash). (CVE-2020-27152)

It was discovered that the framebuffer implementation in the Linux kernel
did not properly perform range checks in certain situations. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2020-28915)

It was discovered that Power 9 processors could be coerced to expose
information from the L1 cache in certain situations. A local attacker could
use this to expose sensitive information. (CVE-2020-4788)


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:


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