ESB-2026.4842

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.4842 USN-8255-1: Linux kernel vulnerabilities 8 May 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: Linux kernel Publisher: Ubuntu Operating System: Ubuntu Resolution: Patch/Upgrade CVE Names: CVE-2026-23273 CVE-2023-32629 CVE-2023-2640 CVE-2026-23112 Original Bulletin: https://ubuntu.com/security/notices/USN-8255-1 Comment: CVSS (Max): 9.8 CVE-2026-23112 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) CVSS Source: Ubuntu Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H EPSS (Max): 91.5% (99th) CVE-2023-2640 2026-05-07 - --------------------------BEGIN INCLUDED TEXT-------------------- USN-8255-1: Linux kernel vulnerabilities Publication date 7 May 2026 Overview Several security issues were fixed in the Linux kernel. Releases 22.04 LTS 20.04 LTS --------------------------------------------------------------------------------- Open side navigation Packages o linux - Linux kernel o linux-aws - Linux kernel for Amazon Web Services (AWS) systems o linux-aws-5.15 - Linux kernel for Amazon Web Services (AWS) systems o linux-aws-fips - Linux kernel for Amazon Web Services (AWS) systems with FIPS o linux-azure - Linux kernel for Microsoft Azure Cloud systems o linux-azure-fips - Linux kernel for Microsoft Azure Cloud systems with FIPS o linux-fips - Linux kernel with FIPS o linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems o linux-gcp-fips - Linux kernel for Google Cloud Platform (GCP) systems with FIPS o linux-gke - Linux kernel for Google Container Engine (GKE) systems o linux-gkeop - Linux kernel for Google Container Engine (GKE) systems o linux-hwe-5.15 - Linux hardware enablement (HWE) kernel o linux-ibm - Linux kernel for IBM cloud systems o linux-ibm-5.15 - Linux kernel for IBM cloud systems o linux-intel-iot-realtime - Linux kernel for Intel IoT Real-time platforms o linux-intel-iotg - Linux kernel for Intel IoT platforms o linux-intel-iotg-5.15 - Linux kernel for Intel IoT platforms o linux-kvm - Linux kernel for cloud environments o linux-lowlatency - Linux low latency kernel o linux-lowlatency-hwe-5.15 - Linux low latency kernel o linux-nvidia - Linux kernel for NVIDIA systems o linux-nvidia-tegra - Linux kernel for NVIDIA Tegra systems o linux-nvidia-tegra-igx - Linux kernel for NVIDIA Tegra IGX systems o linux-oracle - Linux kernel for Oracle Cloud systems o linux-realtime - Linux kernel for Real-time systems Details Stonejiajia, Shir Tamari and Sagi Tzadik discovered that the OverlayFS implementation in the Ubuntu Linux kernel did not properly perform permission checks in certain situations. A local attacker could possibly use this to gain elevated privileges. ( CVE-2023-2640 ) Shir Tamari and Sagi Tzadik discovered that the OverlayFS implementation in the Ubuntu Linux kernel did not properly perform permission checks in certain situations. A local attacker could possibly use this to gain elevated privileges. ( CVE-2023-32629 ) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: o Network drivers; o NVME drivers Update instructions 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 Package Version Release linux-image-5.15.0-1047-nvidia-tegra-igx - 5.15.0-1047.47 linux-image-5.15.0-1047-nvidia-tegra-igx-rt - 5.15.0-1047.47 linux-image-5.15.0-1058-nvidia-tegra - 5.15.0-1058.58 linux-image-5.15.0-1058-nvidia-tegra-rt - 5.15.0-1058.58 linux-image-5.15.0-1089-gkeop - 5.15.0-1089.97 linux-image-5.15.0-1098-intel-iot-realtime - 5.15.0-1098.100 Real-time Real-time kernel available with Ubuntu Pro. linux-image-5.15.0-1098-kvm - 5.15.0-1098.103 linux-image-5.15.0-1100-ibm - 5.15.0-1100.103 linux-image-5.15.0-1101-intel-iotg - 5.15.0-1101.107 linux-image-5.15.0-1101-nvidia - 5.15.0-1101.102 linux-image-5.15.0-1101-nvidia-lowlatency - 5.15.0-1101.102 linux-image-5.15.0-1102-gke - 5.15.0-1102.108 linux-image-5.15.0-1103-oracle - 5.15.0-1103.109 linux-image-5.15.0-1105-realtime - 5.15.0-1105.114 Real-time Real-time kernel available with Ubuntu Pro. linux-image-5.15.0-1106-aws - 5.15.0-1106.113 linux-image-5.15.0-1106-aws-64k - 5.15.0-1106.113 linux-image-5.15.0-1106-aws-fips - 5.15.0-1106.113+fips1 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-5.15.0-1106-gcp - 5.15.0-1106.115 linux-image-5.15.0-1106-gcp-fips - 5.15.0-1106.115+fips1 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-5.15.0-1111-azure - 5.15.0-1111.120 linux-image-5.15.0-1111-azure-fips - 5.15.0-1111.120+fips1 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-5.15.0-177-fips - 5.15.0-177.187+fips1 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-5.15.0-177-generic - 5.15.0-177.187 linux-image-5.15.0-177-generic-64k - 5.15.0-177.187 linux-image-5.15.0-177-generic-lpae - 5.15.0-177.187 linux-image-5.15.0-177-lowlatency - 5.15.0-177.187 linux-image-5.15.0-177-lowlatency-64k - 5.15.0-177.187 linux-image-aws-5.15 - 5.15.0.1106.109 linux-image-aws-64k-5.15 - 5.15.0.1106.109 linux-image-aws-64k-lts-22.04 - 5.15.0.1106.109 linux-image-aws-fips - 5.15.0.1106.102 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-aws-fips-5.15 - 5.15.0.1106.102 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-aws-lts-22.04 - 5.15.0.1106.109 linux-image-azure-5.15 - 5.15.0.1111.109 linux-image-azure-fips - 5.15.0.1111.96 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-azure-fips-5.15 - 5.15.0.1111.96 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-azure-lts-22.04 - 5.15.0.1111.109 22.04 linux-image-fips - 5.15.0.177.103 FIPS Updates FIPS-140 certified LTS package with security fixes. Available with Ubuntu Pro. jammy linux-image-fips-5.15 - 5.15.0.177.103 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-gcp-5.15 - 5.15.0.1106.102 linux-image-gcp-fips - 5.15.0.1106.96 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-gcp-fips-5.15 - 5.15.0.1106.96 FIPS Updates FIPS-140 certified package with security fixes. Available with Ubuntu Pro. linux-image-gcp-lts-22.04 - 5.15.0.1106.102 linux-image-generic - 5.15.0.177.162 linux-image-generic-5.15 - 5.15.0.177.162 linux-image-generic-64k - 5.15.0.177.162 linux-image-generic-64k-5.15 - 5.15.0.177.162 linux-image-generic-lpae - 5.15.0.177.162 linux-image-generic-lpae-5.15 - 5.15.0.177.162 linux-image-gke - 5.15.0.1102.101 linux-image-gke-5.15 - 5.15.0.1102.101 linux-image-gkeop - 5.15.0.1089.88 linux-image-gkeop-5.15 - 5.15.0.1089.88 linux-image-ibm - 5.15.0.1100.96 linux-image-ibm-5.15 - 5.15.0.1100.96 linux-image-intel-iot-realtime - 5.15.0.1098.102 Real-time Real-time kernel available with Ubuntu Pro. linux-image-intel-iot-realtime-5.15 - 5.15.0.1098.102 Real-time Real-time kernel available with Ubuntu Pro. linux-image-intel-iotg - 5.15.0.1101.100 linux-image-intel-iotg-5.15 - 5.15.0.1101.100 linux-image-kvm - 5.15.0.1098.94 linux-image-kvm-5.15 - 5.15.0.1098.94 linux-image-lowlatency - 5.15.0.177.149 linux-image-lowlatency-5.15 - 5.15.0.177.149 linux-image-lowlatency-64k - 5.15.0.177.149 linux-image-lowlatency-64k-5.15 - 5.15.0.177.149 linux-image-nvidia - 5.15.0.1101.101 linux-image-nvidia-5.15 - 5.15.0.1101.101 linux-image-nvidia-lowlatency - 5.15.0.1101.101 linux-image-nvidia-lowlatency-5.15 - 5.15.0.1101.101 linux-image-nvidia-tegra - 5.15.0.1058.58 linux-image-nvidia-tegra-5.15 - 5.15.0.1058.58 linux-image-nvidia-tegra-igx - 5.15.0.1047.49 linux-image-nvidia-tegra-igx-5.15 - 5.15.0.1047.49 linux-image-nvidia-tegra-igx-rt - 5.15.0.1047.49 linux-image-nvidia-tegra-igx-rt-5.15 - 5.15.0.1047.49 linux-image-nvidia-tegra-rt - 5.15.0.1058.58 linux-image-nvidia-tegra-rt-5.15 - 5.15.0.1058.58 linux-image-oracle-5.15 - 5.15.0.1103.99 linux-image-oracle-lts-22.04 - 5.15.0.1103.99 linux-image-realtime - 5.15.0.1105.109 Real-time Real-time kernel available with Ubuntu Pro. linux-image-realtime-5.15 - 5.15.0.1105.109 Real-time Real-time kernel available with Ubuntu Pro. linux-image-virtual - 5.15.0.177.162 linux-image-virtual-5.15 - 5.15.0.177.162 linux-image-5.15.0-1100-ibm - 5.15.0-1100.103~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-1101-intel-iotg - 5.15.0-1101.107~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-1106-aws - 5.15.0-1106.113~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-177-generic - 5.15.0-177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-177-generic-64k - 5.15.0-177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-177-generic-lpae - 5.15.0-177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-177-lowlatency - 5.15.0-177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-5.15.0-177-lowlatency-64k - 5.15.0-177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-aws - 5.15.0.1106.113~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-aws-5.15 - 5.15.0.1106.113~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-generic-5.15 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-generic-64k-5.15 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-generic-64k-hwe-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-generic-hwe-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-generic-lpae-5.15 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix 20.04 available with Ubuntu Pro . LTS linux-image-generic-lpae-hwe-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro focal Fix available with Ubuntu Pro . linux-image-ibm - 5.15.0.1100.103~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-ibm-5.15 - 5.15.0.1100.103~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-intel - 5.15.0.1101.107~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-intel-iotg - 5.15.0.1101.107~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-intel-iotg-5.15 - 5.15.0.1101.107~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-lowlatency-5.15 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-lowlatency-64k-5.15 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-lowlatency-64k-hwe-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-lowlatency-hwe-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-oem-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-oem-20.04b - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-oem-20.04c - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-oem-20.04d - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-virtual-5.15 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . linux-image-virtual-hwe-20.04 - 5.15.0.177.187~20.04.1 Ubuntu Pro Fix available with Ubuntu Pro . --------------------------------------------------------------------------------- References o CVE-2026-23273 o CVE-2026-23112 o CVE-2023-32629 o CVE-2023-2640 Related notices o USN-8254-1 o USN-8245-1 o USN-8244-1 o USN-6285-1 o USN-6261-1 o USN-6260-1 o USN-6251-1 o USN-6250-1 o USN-6248-1 o LSN-0097-1 --------------------------------------------------------------------------------- - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. 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