1. Ubuntu Security Notices
  2. USN-5039-1

USN-5039-1: Linux kernel vulnerability

Publication date

12 August 2021

Overview

The system could be made to crash or run programs as an administrator.

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

Andy Nguyen discovered that the netfilter subsystem in the Linux kernel
contained an out-of-bounds write in its setsockopt() implementation. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code.

Andy Nguyen discovered that the netfilter subsystem in the Linux kernel
contained an out-of-bounds write in its setsockopt() implementation. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code.

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
16.04 xenial linux-image-4.4.0-1096-kvm –  4.4.0-1096.105  
linux-image-4.4.0-1131-aws –  4.4.0-1131.145  
linux-image-4.4.0-213-generic –  4.4.0-213.245  
linux-image-4.4.0-213-lowlatency –  4.4.0-213.245  
linux-image-aws –  4.4.0.1131.136  
linux-image-generic –  4.4.0.213.220  
linux-image-kvm –  4.4.0.1096.94  
linux-image-lowlatency –  4.4.0.213.220  
linux-image-virtual –  4.4.0.213.220  
14.04 trusty linux-image-3.13.0-187-generic –  3.13.0-187.238  
linux-image-3.13.0-187-generic-lpae –  3.13.0-187.238  
linux-image-3.13.0-187-lowlatency –  3.13.0-187.238  
linux-image-4.4.0-1095-aws –  4.4.0-1095.100  
linux-image-4.4.0-213-generic –  4.4.0-213.245~14.04.1  
linux-image-4.4.0-213-lowlatency –  4.4.0-213.245~14.04.1  
linux-image-aws –  4.4.0.1095.93  
linux-image-generic –  3.13.0.187.196  
linux-image-generic-lpae –  3.13.0.187.196  
linux-image-generic-lts-xenial –  4.4.0.213.186  
linux-image-lowlatency –  3.13.0.187.196  
linux-image-lowlatency-lts-xenial –  4.4.0.213.186  
linux-image-server –  3.13.0.187.196  
linux-image-virtual –  3.13.0.187.196  
linux-image-virtual-lts-xenial –  4.4.0.213.186  

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References

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