========================================================================== Ubuntu Security Notice USN-4679-1 January 06, 2021 linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp, linux-gcp-5.4, linux-gke-5.4, linux-hwe-5.4, linux-kvm, linux-oracle, linux-oracle-5.4, linux-raspi, linux-raspi-5.4 vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 20.04 LTS - Ubuntu 18.04 LTS 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: Linux kernel for Microsoft Azure Cloud systems - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - linux-kvm: Linux kernel for cloud environments - linux-oracle: Linux kernel for Oracle Cloud systems - linux-raspi: Linux kernel for Raspberry Pi (V8) systems - linux-aws-5.4: Linux kernel for Amazon Web Services (AWS) systems - linux-azure-5.4: Linux kernel for Microsoft Azure cloud systems - linux-gcp-5.4: Linux kernel for Google Cloud Platform (GCP) systems - linux-gke-5.4: Linux kernel for Google Container Engine (GKE) systems - linux-hwe-5.4: Linux hardware enablement (HWE) kernel - linux-oracle-5.4: Linux kernel for Oracle Cloud systems - linux-raspi-5.4: Linux kernel for Raspberry Pi (V8) systems Details: It was discovered that the console keyboard driver in the Linux kernel contained a race condition. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-25656) Minh Yuan discovered that the tty driver in the Linux kernel contained race conditions when handling fonts. A local attacker could possibly use this to expose sensitive information (kernel memory). (CVE-2020-25668) Kiyin (尹亮) discovered that the perf subsystem in the Linux kernel did not properly deallocate memory in some situations. A privileged attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2020-25704) Jinoh Kang discovered that the Xen event channel infrastructure in the Linux kernel contained a race condition. An attacker in guest could possibly use this to cause a denial of service (dom0 crash). (CVE-2020-27675) Daniel Axtens discovered that PowerPC RTAS implementation in the Linux kernel did not properly restrict memory accesses in some situations. A privileged local attacker could use this to arbitrarily modify kernel memory, potentially bypassing kernel lockdown restrictions. (CVE-2020-27777) Minh Yuan discovered that the framebuffer console driver in the Linux kernel did not properly handle fonts in some conditions. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-28974) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 20.04 LTS: linux-image-5.4.0-1026-raspi 5.4.0-1026.29 linux-image-5.4.0-1031-kvm 5.4.0-1031.32 linux-image-5.4.0-1033-gcp 5.4.0-1033.35 linux-image-5.4.0-1034-aws 5.4.0-1034.35 linux-image-5.4.0-1034-oracle 5.4.0-1034.36 linux-image-5.4.0-1035-azure 5.4.0-1035.36 linux-image-5.4.0-59-generic 5.4.0-59.65 linux-image-5.4.0-59-generic-lpae 5.4.0-59.65 linux-image-5.4.0-59-lowlatency 5.4.0-59.65 linux-image-aws 5.4.0.1034.35 linux-image-azure 5.4.0.1035.33 linux-image-gcp 5.4.0.1033.42 linux-image-generic 5.4.0.59.62 linux-image-generic-lpae 5.4.0.59.62 linux-image-kvm 5.4.0.1031.29 linux-image-lowlatency 5.4.0.59.62 linux-image-oem 5.4.0.59.62 linux-image-oem-osp1 5.4.0.59.62 linux-image-oracle 5.4.0.1034.31 linux-image-raspi 5.4.0.1026.61 linux-image-raspi2 5.4.0.1026.61 linux-image-virtual 5.4.0.59.62 Ubuntu 18.04 LTS: linux-image-5.4.0-1026-raspi 5.4.0-1026.29~18.04.1 linux-image-5.4.0-1033-gcp 5.4.0-1033.35~18.04.1 linux-image-5.4.0-1033-gke 5.4.0-1033.35~18.04.1 linux-image-5.4.0-1034-aws 5.4.0-1034.35~18.04.1 linux-image-5.4.0-1034-oracle 5.4.0-1034.36~18.04.1 linux-image-5.4.0-1035-azure 5.4.0-1035.36~18.04.1 linux-image-5.4.0-59-generic 5.4.0-59.65~18.04.1 linux-image-5.4.0-59-generic-lpae 5.4.0-59.65~18.04.1 linux-image-5.4.0-59-lowlatency 5.4.0-59.65~18.04.1 linux-image-aws 5.4.0.1034.19 linux-image-azure 5.4.0.1035.17 linux-image-gcp 5.4.0.1033.21 linux-image-generic-hwe-18.04 5.4.0.59.65~18.04.54 linux-image-generic-lpae-hwe-18.04 5.4.0.59.65~18.04.54 linux-image-gke-5.4 5.4.0.1033.35~18.04.2 linux-image-lowlatency-hwe-18.04 5.4.0.59.65~18.04.54 linux-image-oem 5.4.0.59.65~18.04.54 linux-image-oem-osp1 5.4.0.59.65~18.04.54 linux-image-oracle 5.4.0.1034.36~18.04.18 linux-image-raspi-hwe-18.04 5.4.0.1026.30 linux-image-snapdragon-hwe-18.04 5.4.0.59.65~18.04.54 linux-image-virtual-hwe-18.04 5.4.0.59.65~18.04.54 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://usn.ubuntu.com/4679-1 CVE-2020-25656, CVE-2020-25668, CVE-2020-25704, CVE-2020-27675, CVE-2020-27777, CVE-2020-28974 Package Information: https://launchpad.net/ubuntu/+source/linux/5.4.0-59.65 https://launchpad.net/ubuntu/+source/linux-aws/5.4.0-1034.35 https://launchpad.net/ubuntu/+source/linux-azure/5.4.0-1035.36 https://launchpad.net/ubuntu/+source/linux-gcp/5.4.0-1033.35 https://launchpad.net/ubuntu/+source/linux-kvm/5.4.0-1031.32 https://launchpad.net/ubuntu/+source/linux-oracle/5.4.0-1034.36 https://launchpad.net/ubuntu/+source/linux-raspi/5.4.0-1026.29 https://launchpad.net/ubuntu/+source/linux-aws-5.4/5.4.0-1034.35~18.04.1 https://launchpad.net/ubuntu/+source/linux-azure-5.4/5.4.0-1035.36~18.04.1 https://launchpad.net/ubuntu/+source/linux-gcp-5.4/5.4.0-1033.35~18.04.1 https://launchpad.net/ubuntu/+source/linux-gke-5.4/5.4.0-1033.35~18.04.1 https://launchpad.net/ubuntu/+source/linux-hwe-5.4/5.4.0-59.65~18.04.1 https://launchpad.net/ubuntu/+source/linux-oracle-5.4/5.4.0-1034.36~18.04.1 https://launchpad.net/ubuntu/+source/linux-raspi-5.4/5.4.0-1026.29~18.04.1