--- title: 'USN-6446-2: Linux kernel vulnerabilities | 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-6446-2 --- 1. [Ubuntu Security Notices](https://ubuntu.com/security/notices) 2. USN-6446-2 --- # USN-6446-2: Linux kernel vulnerabilities Publication date 24 October 2023 Overview Several security issues were fixed in the Linux kernel. Releases [20.04 LTS](https://ubuntu.com/security/notices?release=focal) --- Open side navigation ## Packages * [linux-gcp-5.15](https://ubuntu.com/security/cves?package=linux-gcp-5.15) - Linux kernel for Google Cloud Platform (GCP) systems * [linux-gkeop-5.15](https://ubuntu.com/security/cves?package=linux-gkeop-5.15) - Linux kernel for Google Container Engine (GKE) systems ## Details Ross Lagerwall discovered that the Xen netback backend driver in the Linux kernel did not properly handle certain unusual packets from a paravirtualized network frontend, leading to a buffer overflow. An attacker in a guest VM could use this to cause a denial of service (host system crash) or possibly execute arbitrary code. ([CVE-2023-34319](https://ubuntu.com/security/CVE-2023-34319)) Bien Pham discovered that the netfiler subsystem in the Linux kernel contained a race condition, leading to a use-after-free vulnerability. A local user could use this to cause a denial of service (system crash) or possibly execute arbitrary code. ([CVE-2023-4244](https://ubuntu.com/security/CVE-2023-4244)) Kyle Zeng discovered that the networking stack implementation in the Linux kernel did not properly validate skb object size in certain conditions. An attacker could use this cause a denial of service (system crash) or possibly execute arbitrary code. ( --- Show more ## 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 | | --- | --- | | 20.04 LTS focal | [linux-image-5.15.0-1031-gkeop](https://launchpad.net/ubuntu/+source/linux-signed-gkeop-5.15) –  [5.15.0-1031.37~20.04.1](https://launchpad.net/ubuntu/+source/linux-signed-gkeop-5.15/5.15.0-1031.37~20.04.1) | | | | [linux-image-5.15.0-1045-gcp](https://launchpad.net/ubuntu/+source/linux-signed-gcp-5.15) –  [5.15.0-1045.53~20.04.2](https://launchpad.net/ubuntu/+source/linux-signed-gcp-5.15/5.15.0-1045.53~20.04.2) | | | | [linux-image-gcp](https://launchpad.net/ubuntu/+source/linux-meta-gcp-5.15) –  [5.15.0.1045.53~20.04.1](https://launchpad.net/ubuntu/+source/linux-meta-gcp-5.15/5.15.0.1045.53~20.04.1) | | | | [linux-image-gkeop-5.15](https://launchpad.net/ubuntu/+source/linux-meta-gkeop-5.15) –  [5.15.0.1031.37~20.04.27](https://launchpad.net/ubuntu/+source/linux-meta-gkeop-5.15/5.15.0.1031.37~20.04.27) | | | --- ### 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-2023-5197](https://ubuntu.com/security/CVE-2023-5197) * [CVE-2023-4921](https://ubuntu.com/security/CVE-2023-4921) * [CVE-2023-4881](https://ubuntu.com/security/CVE-2023-4881) * [CVE-2023-4623](https://ubuntu.com/security/CVE-2023-4623) * [CVE-2023-4622](https://ubuntu.com/security/CVE-2023-4622) * [CVE-2023-42756](https://ubuntu.com/security/CVE-2023-42756) * [CVE-2023-42755](https://ubuntu.com/security/CVE-2023-42755) * [CVE-2023-42753](https://ubuntu.com/security/CVE-2023-42753) * [CVE-2023-42752](https://ubuntu.com/security/CVE-2023-42752) * [CVE-2023-4244](https://ubuntu.com/security/CVE-2023-4244) --- Show 1 more references ## Related notices id="usn" *Search* * [USN-6716-1](https://ubuntu.com/security/notices/USN-6716-1) * [USN-6699-1](https://ubuntu.com/security/notices/USN-6699-1) * [USN-6681-1](https://ubuntu.com/security/notices/USN-6681-1) * [USN-6681-2](https://ubuntu.com/security/notices/USN-6681-2) * [USN-6681-3](https://ubuntu.com/security/notices/USN-6681-3) * [USN-6681-4](https://ubuntu.com/security/notices/USN-6681-4) * [USN-6572-1](https://ubuntu.com/security/notices/USN-6572-1) * [USN-6537-1](https://ubuntu.com/security/notices/USN-6537-1) * [USN-6503-1](https://ubuntu.com/security/notices/USN-6503-1) * [USN-6479-1](https://ubuntu.com/security/notices/USN-6479-1) --- Show 26 more references --- Have additional questions? 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