========================================================================= Ubuntu Security Notice USN-4750-1 February 25, 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-gkeop, linux-gkeop-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-gkeop: Linux kernel for Google Container Engine (GKE) 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-gkeop-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: Bodong Zhao discovered a use-after-free in the Sun keyboard driver implementation in the Linux kernel. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2020-25669) It was discovered that the jfs file system implementation in the Linux kernel contained an out-of-bounds read vulnerability. A local attacker could use this to possibly cause a denial of service (system crash). (CVE-2020-27815) Shisong Qin and Bodong Zhao discovered that Speakup screen reader driver in the Linux kernel did not correctly handle setting line discipline in some situations. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-27830, CVE-2020-28941) It was discovered that an information leak existed in the syscall implementation in the Linux kernel on 32 bit systems. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-28588) Michael Kurth and Pawel Wieczorkiewicz discovered that the Xen event processing backend in the Linux kernel did not properly limit the number of events queued. An attacker in a guest VM could use this to cause a denial of service in the host OS. (CVE-2020-29568) Olivier Benjamin and Pawel Wieczorkiewicz discovered a race condition the Xen paravirt block backend in the Linux kernel, leading to a use-after-free vulnerability. An attacker in a guest VM could use this to cause a denial of service in the host OS. (CVE-2020-29569) Jann Horn discovered that the tty subsystem of the Linux kernel did not use consistent locking in some situations, leading to a read-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-29660) Jann Horn discovered a race condition in the tty subsystem of the Linux kernel in the locking for the TIOCSPGRP ioctl(), leading to a use-after- free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-29661) It was discovered that the netfilter subsystem in the Linux kernel did not properly handle filter rules in some situations. A local attacker with the CAP_NET_ADMIN capability could use this to cause a denial of service. (CVE-2021-20177) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 20.04 LTS: linux-image-5.4.0-1010-gkeop 5.4.0-1010.11 linux-image-5.4.0-1029-raspi 5.4.0-1029.32 linux-image-5.4.0-1033-kvm 5.4.0-1033.34 linux-image-5.4.0-1037-gcp 5.4.0-1037.40 linux-image-5.4.0-1038-aws 5.4.0-1038.40 linux-image-5.4.0-1038-oracle 5.4.0-1038.41 linux-image-5.4.0-1040-azure 5.4.0-1040.42 linux-image-5.4.0-66-generic 5.4.0-66.74 linux-image-5.4.0-66-generic-lpae 5.4.0-66.74 linux-image-5.4.0-66-lowlatency 5.4.0-66.74 linux-image-aws 5.4.0.1038.39 linux-image-azure 5.4.0.1040.38 linux-image-gcp 5.4.0.1037.46 linux-image-generic 5.4.0.66.69 linux-image-generic-lpae 5.4.0.66.69 linux-image-gkeop 5.4.0.1010.13 linux-image-gkeop-5.4 5.4.0.1010.13 linux-image-kvm 5.4.0.1033.31 linux-image-lowlatency 5.4.0.66.69 linux-image-oem 5.4.0.66.69 linux-image-oem-osp1 5.4.0.66.69 linux-image-oracle 5.4.0.1038.35 linux-image-raspi 5.4.0.1029.64 linux-image-raspi2 5.4.0.1029.64 linux-image-virtual 5.4.0.66.69 Ubuntu 18.04 LTS: linux-image-5.4.0-1010-gkeop 5.4.0-1010.11~18.04.1 linux-image-5.4.0-1029-raspi 5.4.0-1029.32~18.04.1 linux-image-5.4.0-1036-gke 5.4.0-1036.38~18.04.1 linux-image-5.4.0-1037-gcp 5.4.0-1037.40~18.04.1 linux-image-5.4.0-1038-aws 5.4.0-1038.40~18.04.1 linux-image-5.4.0-1038-oracle 5.4.0-1038.41~18.04.1 linux-image-5.4.0-1040-azure 5.4.0-1040.42~18.04.1 linux-image-5.4.0-66-generic 5.4.0-66.74~18.04.2 linux-image-5.4.0-66-generic-lpae 5.4.0-66.74~18.04.2 linux-image-5.4.0-66-lowlatency 5.4.0-66.74~18.04.2 linux-image-aws 5.4.0.1038.22 linux-image-azure 5.4.0.1040.20 linux-image-gcp 5.4.0.1037.24 linux-image-generic-hwe-18.04 5.4.0.66.74~18.04.61 linux-image-generic-lpae-hwe-18.04 5.4.0.66.74~18.04.61 linux-image-gke-5.4 5.4.0.1036.38~18.04.4 linux-image-gkeop-5.4 5.4.0.1010.11~18.04.11 linux-image-lowlatency-hwe-18.04 5.4.0.66.74~18.04.61 linux-image-oem 5.4.0.66.74~18.04.61 linux-image-oem-osp1 5.4.0.66.74~18.04.61 linux-image-oracle 5.4.0.1038.41~18.04.21 linux-image-raspi-hwe-18.04 5.4.0.1029.32 linux-image-snapdragon-hwe-18.04 5.4.0.66.74~18.04.61 linux-image-virtual-hwe-18.04 5.4.0.66.74~18.04.61 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/4750-1 CVE-2020-25669, CVE-2020-27815, CVE-2020-27830, CVE-2020-28588, CVE-2020-28941, CVE-2020-29568, CVE-2020-29569, CVE-2020-29660, CVE-2020-29661, CVE-2021-20177 Package Information: https://launchpad.net/ubuntu/+source/linux/5.4.0-66.74 https://launchpad.net/ubuntu/+source/linux-aws/5.4.0-1038.40 https://launchpad.net/ubuntu/+source/linux-azure/5.4.0-1040.42 https://launchpad.net/ubuntu/+source/linux-gcp/5.4.0-1037.40 https://launchpad.net/ubuntu/+source/linux-gkeop/5.4.0-1010.11 https://launchpad.net/ubuntu/+source/linux-kvm/5.4.0-1033.34 https://launchpad.net/ubuntu/+source/linux-oracle/5.4.0-1038.41 https://launchpad.net/ubuntu/+source/linux-raspi/5.4.0-1029.32 https://launchpad.net/ubuntu/+source/linux-aws-5.4/5.4.0-1038.40~18.04.1 https://launchpad.net/ubuntu/+source/linux-azure-5.4/5.4.0-1040.42~18.04.1 https://launchpad.net/ubuntu/+source/linux-gcp-5.4/5.4.0-1037.40~18.04.1 https://launchpad.net/ubuntu/+source/linux-gke-5.4/5.4.0-1036.38~18.04.1 https://launchpad.net/ubuntu/+source/linux-gkeop-5.4/5.4.0-1010.11~18.04.1 https://launchpad.net/ubuntu/+source/linux-hwe-5.4/5.4.0-66.74~18.04.2 https://launchpad.net/ubuntu/+source/linux-oracle-5.4/5.4.0-1038.41~18.04.1 https://launchpad.net/ubuntu/+source/linux-raspi-5.4/5.4.0-1029.32~18.04.1