--- title: 'USN-5062-1: Linux kernel vulnerability | Ubuntu security notices' description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/notices/USN-5062-1 --- 1. [Ubuntu Security Notices](https://ubuntu.com/security/notices) 2. USN-5062-1 --- # USN-5062-1: Linux kernel vulnerability Publication date 8 September 2021 Overview The system could be made to crash or run programs as an administrator. Releases [16.04 LTS](https://ubuntu.com/security/notices?release=xenial) [14.04 LTS](https://ubuntu.com/security/notices?release=trusty) --- Open side navigation ## Packages * [linux](https://ubuntu.com/security/cves?package=linux) - Linux kernel * [linux-aws](https://ubuntu.com/security/cves?package=linux-aws) - Linux kernel for Amazon Web Services (AWS) systems * [linux-kvm](https://ubuntu.com/security/cves?package=linux-kvm) - Linux kernel for cloud environments * [linux-lts-xenial](https://ubuntu.com/security/cves?package=linux-lts-xenial) - Linux hardware enablement kernel from Xenial for Trusty ## Details Maxim Levitsky discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not properly prevent a guest VM from enabling AVIC in nested guest VMs. An attacker in a guest VM could use this to write to portions of the host's physical memory. ## 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.](https://ubuntu.com/security/cves/about#security) 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 LTS xenial | [linux-image-4.4.0-1097-kvm](https://launchpad.net/ubuntu/+source/linux-kvm) –  4.4.0-1097.106   Ubuntu Pro | | | | [linux-image-4.4.0-1132-aws](https://launchpad.net/ubuntu/+source/linux-aws) –  4.4.0-1132.146   Ubuntu Pro | | | | [linux-image-4.4.0-214-generic](https://launchpad.net/ubuntu/+source/linux-signed) –  4.4.0-214.246   Ubuntu Pro | | | | [linux-image-4.4.0-214-lowlatency](https://launchpad.net/ubuntu/+source/linux-signed) –  4.4.0-214.246   Ubuntu Pro | | | | [linux-image-aws](https://launchpad.net/ubuntu/+source/linux-meta-aws) –  4.4.0.1132.137   Ubuntu Pro | | | | [linux-image-generic](https://launchpad.net/ubuntu/+source/linux-meta) –  4.4.0.214.221   Ubuntu Pro | | | | [linux-image-kvm](https://launchpad.net/ubuntu/+source/linux-meta-kvm) –  4.4.0.1097.95   Ubuntu Pro | | | | [linux-image-lowlatency](https://launchpad.net/ubuntu/+source/linux-meta) –  4.4.0.214.221   Ubuntu Pro | | | | [linux-image-virtual](https://launchpad.net/ubuntu/+source/linux-meta) –  4.4.0.214.221   Ubuntu Pro | | | | 14.04 LTS trusty | [linux-image-4.4.0-1096-aws](https://launchpad.net/ubuntu/+source/linux-aws) –  4.4.0-1096.101   Ubuntu Pro | | | | [linux-image-4.4.0-214-generic](https://launchpad.net/ubuntu/+source/linux-signed-lts-xenial) –  4.4.0-214.246~14.04.1   Ubuntu Pro | | | | [linux-image-4.4.0-214-lowlatency](https://launchpad.net/ubuntu/+source/linux-signed-lts-xenial) –  4.4.0-214.246~14.04.1   Ubuntu Pro | | | | [linux-image-aws](https://launchpad.net/ubuntu/+source/linux-meta-aws) –  4.4.0.1096.94   Ubuntu Pro | | | | [linux-image-generic-lts-xenial](https://launchpad.net/ubuntu/+source/linux-meta-lts-xenial) –  4.4.0.214.187   Ubuntu Pro | | | | [linux-image-lowlatency-lts-xenial](https://launchpad.net/ubuntu/+source/linux-meta-lts-xenial) –  4.4.0.214.187   Ubuntu Pro | | | | [linux-image-virtual-lts-xenial](https://launchpad.net/ubuntu/+source/linux-meta-lts-xenial) –  4.4.0.214.187   Ubuntu Pro | | | --- ### 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](https://ubuntu.com/pro) ## References * [CVE-2021-3653](https://ubuntu.com/security/CVE-2021-3653) ## Related notices * [USN-5082-1](https://ubuntu.com/security/notices/USN-5082-1) * [USN-5073-1](https://ubuntu.com/security/notices/USN-5073-1) * [USN-5073-2](https://ubuntu.com/security/notices/USN-5073-2) * [USN-5072-1](https://ubuntu.com/security/notices/USN-5072-1) * [USN-5071-1](https://ubuntu.com/security/notices/USN-5071-1) * [USN-5071-2](https://ubuntu.com/security/notices/USN-5071-2) * [USN-5070-1](https://ubuntu.com/security/notices/USN-5070-1) * [LSN-0083-1](https://ubuntu.com/security/notices/LSN-0083-1) * [LSN-0081-1](https://ubuntu.com/security/notices/LSN-0081-1) --- Have additional questions? [Talk to a member of the team ›](https://wiki.ubuntu.com/SecurityTeam/FAQ?_ga=2.242131138.1744859116.1742138161-1500419473.1726851136&_gl=1*161muja*_gcl_au*MzUyMTIzNjI1LjE3MzYyNDQ4NTE.#Contact)