--- title: 'USN-8620-1: 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-8620-1 --- 1. [Ubuntu Security Notices](https://ubuntu.com/security/notices) 2. USN-8620-1 --- # USN-8620-1: Linux kernel vulnerabilities Publication date 28 July 2026 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-azure-5.15](https://ubuntu.com/security/cves?package=linux-azure-5.15) - Linux kernel for Microsoft Azure cloud systems * [linux-azure-fde-5.15](https://ubuntu.com/security/cves?package=linux-azure-fde-5.15) - Linux kernel for Microsoft Azure CVM cloud systems * [linux-oracle-5.15](https://ubuntu.com/security/cves?package=linux-oracle-5.15) - Linux kernel for Oracle Cloud systems ## Details Maxim Suhanov discovered that the NTFS file system implementation in the Linux kernel did not properly validate file name length in certain situations, leading to an out-of-bounds read. An attacker could use this to construct a malicious NTFS image that, when mounted and operated on, could expose sensitive information (kernel memory). ([CVE-2023-45896](https://ubuntu.com/security/CVE-2023-45896)) It was discovered that some AMD processors did not properly clear data in the floating point divider unit during speculative execution. A local attacker could use this to expose sensitive information. ([CVE-2025-54505](https://ubuntu.com/security/CVE-2025-54505)) It was discovered that some AMD Zen 2 processors did not properly isolate shared resources in the operation cache. A local attacker could possibly use this issue to corrupt instructions executed at a higher privilege level, resulting in privilege escalation. ( --- 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-5.15.0-1109-oracle](https://launchpad.net/ubuntu/+source/linux-signed-oracle-5.15) –  5.15.0-1109.115~20.04.1   Ubuntu Pro | | | | [linux-image-5.15.0-1117-azure](https://launchpad.net/ubuntu/+source/linux-signed-azure-5.15) –  5.15.0-1117.126~20.04.1   Ubuntu Pro | | | | [linux-image-5.15.0-1117-azure-fde](https://launchpad.net/ubuntu/+source/linux-signed-azure-fde-5.15) –  5.15.0-1117.126~20.04.2   Ubuntu Pro | | | | [linux-image-azure](https://launchpad.net/ubuntu/+source/linux-meta-azure-5.15) –  5.15.0.1117.126~20.04.1   Ubuntu Pro | | | | [linux-image-azure-5.15](https://launchpad.net/ubuntu/+source/linux-meta-azure-5.15) –  5.15.0.1117.126~20.04.1   Ubuntu Pro | | | | [linux-image-azure-cvm](https://launchpad.net/ubuntu/+source/linux-meta-azure-5.15) –  5.15.0.1117.126~20.04.1   Ubuntu Pro | | | | [linux-image-azure-fde](https://launchpad.net/ubuntu/+source/linux-meta-azure-fde-5.15) –  5.15.0.1117.126~20.04.2   Ubuntu Pro | | | | [linux-image-azure-fde-5.15](https://launchpad.net/ubuntu/+source/linux-meta-azure-fde-5.15) –  5.15.0.1117.126~20.04.2   Ubuntu Pro | | | | [linux-image-oracle](https://launchpad.net/ubuntu/+source/linux-meta-oracle-5.15) –  5.15.0.1109.115~20.04.1   Ubuntu Pro | | | | [linux-image-oracle-5.15](https://launchpad.net/ubuntu/+source/linux-meta-oracle-5.15) –  5.15.0.1109.115~20.04.1   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 *Search* * [CVE-2026-64221](https://ubuntu.com/security/CVE-2026-64221) * [CVE-2026-64220](https://ubuntu.com/security/CVE-2026-64220) * [CVE-2026-64219](https://ubuntu.com/security/CVE-2026-64219) * [CVE-2026-64218](https://ubuntu.com/security/CVE-2026-64218) * [CVE-2026-64185](https://ubuntu.com/security/CVE-2026-64185) * [CVE-2026-64179](https://ubuntu.com/security/CVE-2026-64179) * [CVE-2026-64178](https://ubuntu.com/security/CVE-2026-64178) * [CVE-2026-64177](https://ubuntu.com/security/CVE-2026-64177) * [CVE-2026-64174](https://ubuntu.com/security/CVE-2026-64174) * [CVE-2026-64173](https://ubuntu.com/security/CVE-2026-64173) --- Show 752 more references ## Related notices id="usn" *Search* * [USN-8850-1](https://ubuntu.com/security/notices/USN-8850-1) * [USN-8802-1](https://ubuntu.com/security/notices/USN-8802-1) * [USN-8793-1](https://ubuntu.com/security/notices/USN-8793-1) * [USN-8793-2](https://ubuntu.com/security/notices/USN-8793-2) * [USN-8781-1](https://ubuntu.com/security/notices/USN-8781-1) * [USN-8761-1](https://ubuntu.com/security/notices/USN-8761-1) * [USN-8761-2](https://ubuntu.com/security/notices/USN-8761-2) * [USN-8761-3](https://ubuntu.com/security/notices/USN-8761-3) * [USN-8748-1](https://ubuntu.com/security/notices/USN-8748-1) * [USN-8729-1](https://ubuntu.com/security/notices/USN-8729-1) --- Show 278 more references --- Have additional questions? 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