1. Ubuntu Security Notices
  2. USN-5003-1

USN-5003-1: Linux kernel vulnerabilities

Publication date

23 June 2021

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-aws-hwe - Linux kernel for Amazon Web Services (AWS-HWE) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-azure-4.15 - Linux kernel for Microsoft Azure Cloud systems
  • linux-dell300x - Linux kernel for Dell 300x platforms
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gcp-4.15 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi (V8) systems
  • linux-snapdragon - Linux kernel for Qualcomm Snapdragon processors

Details

Norbert Slusarek discovered a race condition in the CAN BCM networking
protocol of the Linux kernel leading to multiple use-after-free
vulnerabilities. A local attacker could use this issue to execute arbitrary
code. (CVE-2021-3609)

It was discovered that the eBPF implementation in the Linux kernel did not
properly track bounds information for 32 bit registers when performing div
and mod operations. A local attacker could use this to possibly execute
arbitrary code. (CVE-2021-3600)

Or Cohen discovered that the SCTP implementation in the Linux kernel
contained a race condition in some situations, leading to a use-after-free
condition. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2021-23133)

Norbert Slusarek discovered a race condition in the CAN BCM networking
protocol of the Linux kernel leading to multiple use-after-free
vulnerabilities. A local attacker could use this issue to execute arbitrary
code. (CVE-2021-3609)

It was discovered that the eBPF implementation in the Linux kernel did not
properly track bounds information for 32 bit registers when performing div
and mod operations. A local attacker could use this to possibly execute
arbitrary code. (CVE-2021-3600)

Or Cohen discovered that the SCTP implementation in the Linux kernel
contained a race condition in some situations, leading to a use-after-free
condition. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2021-23133)

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
18.04 bionic linux-image-4.15.0-1022-dell300x –  4.15.0-1022.26
linux-image-4.15.0-1075-oracle –  4.15.0-1075.83
linux-image-4.15.0-1089-raspi2 –  4.15.0-1089.94
linux-image-4.15.0-1103-gcp –  4.15.0-1103.116
linux-image-4.15.0-1106-aws –  4.15.0-1106.113
linux-image-4.15.0-1106-snapdragon –  4.15.0-1106.115
linux-image-4.15.0-1118-azure –  4.15.0-1118.131
linux-image-4.15.0-147-generic –  4.15.0-147.151
linux-image-4.15.0-147-generic-lpae –  4.15.0-147.151
linux-image-4.15.0-147-lowlatency –  4.15.0-147.151
linux-image-aws-lts-18.04 –  4.15.0.1106.109
linux-image-azure-lts-18.04 –  4.15.0.1118.91
linux-image-dell300x –  4.15.0.1022.24
linux-image-gcp-lts-18.04 –  4.15.0.1103.121
linux-image-generic –  4.15.0.147.134
linux-image-generic-lpae –  4.15.0.147.134
linux-image-lowlatency –  4.15.0.147.134
linux-image-oracle-lts-18.04 –  4.15.0.1075.85
linux-image-raspi2 –  4.15.0.1089.86
linux-image-snapdragon –  4.15.0.1106.109
linux-image-virtual –  4.15.0.147.134
16.04 xenial linux-image-4.15.0-1075-oracle –  4.15.0-1075.83~16.04.1  
linux-image-4.15.0-1103-gcp –  4.15.0-1103.116~16.04.1  
linux-image-4.15.0-1106-aws –  4.15.0-1106.113~16.04.1  
linux-image-4.15.0-1118-azure –  4.15.0-1118.131~16.04.1  
linux-image-4.15.0-147-generic –  4.15.0-147.151~16.04.1  
linux-image-4.15.0-147-lowlatency –  4.15.0-147.151~16.04.1  
linux-image-aws-hwe –  4.15.0.1106.97  
linux-image-azure –  4.15.0.1118.109  
linux-image-gcp –  4.15.0.1103.104  
linux-image-generic-hwe-16.04 –  4.15.0.147.143  
linux-image-gke –  4.15.0.1103.104  
linux-image-lowlatency-hwe-16.04 –  4.15.0.147.143  
linux-image-oem –  4.15.0.147.143  
linux-image-oracle –  4.15.0.1075.63  
linux-image-virtual-hwe-16.04 –  4.15.0.147.143  
14.04 trusty linux-image-4.15.0-1118-azure –  4.15.0-1118.131~14.04.1  
linux-image-azure –  4.15.0.1118.91  

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 ›