========================================================================== Ubuntu Security Notice USN-4916-1 April 15, 2021 linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-dell300x, linux-gcp, linux-gcp-4.15, linux-hwe, linux-kvm, linux-lts-xenial, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 18.04 LTS - Ubuntu 16.04 LTS - Ubuntu 14.04 ESM Summary: Several security issues were fixed in the Linux kernel. Software Description: - linux: Linux kernel - linux-aws: Linux kernel for Amazon Web Services (AWS) systems - linux-azure-4.15: Linux kernel for Microsoft Azure Cloud systems - linux-dell300x: Linux kernel for Dell 300x platforms - linux-gcp-4.15: Linux kernel for Google Cloud Platform (GCP) systems - linux-kvm: Linux kernel for cloud environments - linux-oracle: Linux kernel for Oracle Cloud systems - linux-raspi2: Linux kernel for Raspberry Pi (V8) systems - linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors - linux-aws-hwe: Linux kernel for Amazon Web Services (AWS-HWE) systems - linux-azure: Linux kernel for Microsoft Azure Cloud systems - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - linux-hwe: Linux hardware enablement (HWE) kernel - linux-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty Details: It was discovered that the overlayfs implementation in the Linux kernel did not properly validate the application of file system capabilities with respect to user namespaces. A local attacker could use this to gain elevated privileges. (CVE-2021-3493) Piotr Krysiuk discovered that the BPF JIT compiler for x86 in the Linux kernel did not properly validate computation of branch displacements in some situations. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-29154) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 18.04 LTS: linux-image-4.15.0-1017-dell300x 4.15.0-1017.21 linux-image-4.15.0-1070-oracle 4.15.0-1070.78 linux-image-4.15.0-1084-raspi2 4.15.0-1084.89 linux-image-4.15.0-1090-kvm 4.15.0-1090.92 linux-image-4.15.0-1098-gcp 4.15.0-1098.111 linux-image-4.15.0-1099-aws 4.15.0-1099.106 linux-image-4.15.0-1101-snapdragon 4.15.0-1101.110 linux-image-4.15.0-1113-azure 4.15.0-1113.126 linux-image-4.15.0-142-generic 4.15.0-142.146 linux-image-4.15.0-142-generic-lpae 4.15.0-142.146 linux-image-4.15.0-142-lowlatency 4.15.0-142.146 linux-image-aws-lts-18.04 4.15.0.1099.102 linux-image-azure-lts-18.04 4.15.0.1113.86 linux-image-dell300x 4.15.0.1017.19 linux-image-gcp-lts-18.04 4.15.0.1098.116 linux-image-generic 4.15.0.142.129 linux-image-generic-lpae 4.15.0.142.129 linux-image-kvm 4.15.0.1090.86 linux-image-lowlatency 4.15.0.142.129 linux-image-oracle-lts-18.04 4.15.0.1070.80 linux-image-powerpc-e500mc 4.15.0.142.129 linux-image-powerpc-smp 4.15.0.142.129 linux-image-powerpc64-emb 4.15.0.142.129 linux-image-powerpc64-smp 4.15.0.142.129 linux-image-raspi2 4.15.0.1084.81 linux-image-snapdragon 4.15.0.1101.104 linux-image-virtual 4.15.0.142.129 Ubuntu 16.04 LTS: linux-image-4.15.0-1070-oracle 4.15.0-1070.78~16.04.1 linux-image-4.15.0-1098-gcp 4.15.0-1098.111~16.04.1 linux-image-4.15.0-1099-aws 4.15.0-1099.106~16.04.1 linux-image-4.15.0-1113-azure 4.15.0-1113.126~16.04.1 linux-image-4.15.0-142-generic 4.15.0-142.146~16.04.1 linux-image-4.15.0-142-generic-lpae 4.15.0-142.146~16.04.1 linux-image-4.15.0-142-lowlatency 4.15.0-142.146~16.04.1 linux-image-4.4.0-1092-kvm 4.4.0-1092.101 linux-image-4.4.0-1127-aws 4.4.0-1127.141 linux-image-4.4.0-1151-raspi2 4.4.0-1151.162 linux-image-4.4.0-1155-snapdragon 4.4.0-1155.165 linux-image-4.4.0-209-generic 4.4.0-209.241 linux-image-4.4.0-209-generic-lpae 4.4.0-209.241 linux-image-4.4.0-209-lowlatency 4.4.0-209.241 linux-image-4.4.0-209-powerpc-e500mc 4.4.0-209.241 linux-image-4.4.0-209-powerpc-smp 4.4.0-209.241 linux-image-4.4.0-209-powerpc64-emb 4.4.0-209.241 linux-image-4.4.0-209-powerpc64-smp 4.4.0-209.241 linux-image-aws 4.4.0.1127.132 linux-image-aws-hwe 4.15.0.1099.92 linux-image-azure 4.15.0.1113.104 linux-image-gcp 4.15.0.1098.99 linux-image-generic 4.4.0.209.215 linux-image-generic-hwe-16.04 4.15.0.142.137 linux-image-generic-lpae 4.4.0.209.215 linux-image-generic-lpae-hwe-16.04 4.15.0.142.137 linux-image-gke 4.15.0.1098.99 linux-image-kvm 4.4.0.1092.90 linux-image-lowlatency 4.4.0.209.215 linux-image-lowlatency-hwe-16.04 4.15.0.142.137 linux-image-oem 4.15.0.142.137 linux-image-oracle 4.15.0.1070.58 linux-image-powerpc-e500mc 4.4.0.209.215 linux-image-powerpc-smp 4.4.0.209.215 linux-image-powerpc64-emb 4.4.0.209.215 linux-image-powerpc64-smp 4.4.0.209.215 linux-image-raspi2 4.4.0.1151.151 linux-image-snapdragon 4.4.0.1155.147 linux-image-virtual 4.4.0.209.215 linux-image-virtual-hwe-16.04 4.15.0.142.137 Ubuntu 14.04 ESM: linux-image-4.15.0-1113-azure 4.15.0-1113.126~14.04.1 linux-image-4.4.0-1091-aws 4.4.0-1091.95 linux-image-4.4.0-209-generic 4.4.0-209.241~14.04.1 linux-image-4.4.0-209-generic-lpae 4.4.0-209.241~14.04.1 linux-image-4.4.0-209-lowlatency 4.4.0-209.241~14.04.1 linux-image-4.4.0-209-powerpc-e500mc 4.4.0-209.241~14.04.1 linux-image-4.4.0-209-powerpc-smp 4.4.0-209.241~14.04.1 linux-image-4.4.0-209-powerpc64-emb 4.4.0-209.241~14.04.1 linux-image-4.4.0-209-powerpc64-smp 4.4.0-209.241~14.04.1 linux-image-aws 4.4.0.1091.88 linux-image-azure 4.15.0.1113.86 linux-image-generic-lpae-lts-xenial 4.4.0.209.182 linux-image-generic-lts-xenial 4.4.0.209.182 linux-image-lowlatency-lts-xenial 4.4.0.209.182 linux-image-powerpc-e500mc-lts-xenial 4.4.0.209.182 linux-image-powerpc-smp-lts-xenial 4.4.0.209.182 linux-image-powerpc64-emb-lts-xenial 4.4.0.209.182 linux-image-powerpc64-smp-lts-xenial 4.4.0.209.182 linux-image-virtual-lts-xenial 4.4.0.209.182 After a standard system update you need to reboot your computer to make all the necessary changes. 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. References: https://ubuntu.com/security/notices/USN-4916-1 CVE-2021-29154, CVE-2021-3493 Package Information: https://launchpad.net/ubuntu/+source/linux/4.15.0-142.146 https://launchpad.net/ubuntu/+source/linux-aws/4.15.0-1099.106 https://launchpad.net/ubuntu/+source/linux-azure-4.15/4.15.0-1113.126 https://launchpad.net/ubuntu/+source/linux-dell300x/4.15.0-1017.21 https://launchpad.net/ubuntu/+source/linux-gcp-4.15/4.15.0-1098.111 https://launchpad.net/ubuntu/+source/linux-kvm/4.15.0-1090.92 https://launchpad.net/ubuntu/+source/linux-oracle/4.15.0-1070.78 https://launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1084.89 https://launchpad.net/ubuntu/+source/linux-snapdragon/4.15.0-1101.110 https://launchpad.net/ubuntu/+source/linux/4.4.0-209.241 https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1127.141 https://launchpad.net/ubuntu/+source/linux-aws-hwe/4.15.0-1099.106~16.04.1 https://launchpad.net/ubuntu/+source/linux-azure/4.15.0-1113.126~16.04.1 https://launchpad.net/ubuntu/+source/linux-gcp/4.15.0-1098.111~16.04.1 https://launchpad.net/ubuntu/+source/linux-hwe/4.15.0-142.146~16.04.1 https://launchpad.net/ubuntu/+source/linux-kvm/4.4.0-1092.101 https://launchpad.net/ubuntu/+source/linux-oracle/4.15.0-1070.78~16.04.1 https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1151.162 https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1155.165