========================================================================= Ubuntu Security Notice USN-4427-1 July 22, 2020 linux, linux-aws, linux-kvm, linux-lts-xenial, linux-raspi2, linux-snapdragon vulnerabilities ========================================================================= A security issue affects these releases of Ubuntu and its derivatives: - 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-kvm: Linux kernel for cloud environments - linux-raspi2: Linux kernel for Raspberry Pi (V7) systems - linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors - linux-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty Details: It was discovered that the Kvaser CAN/USB driver in the Linux kernel did not properly initialize memory in certain situations. A local attacker could possibly use this to expose sensitive information (kernel memory). (CVE-2019-19947) Chuhong Yuan discovered that go7007 USB audio device driver in the Linux kernel did not properly deallocate memory in some failure conditions. A physically proximate attacker could use this to cause a denial of service (memory exhaustion). (CVE-2019-20810) Jason A. Donenfeld discovered that the ACPI implementation in the Linux kernel did not properly restrict loading SSDT code from an EFI variable. A privileged attacker could use this to bypass Secure Boot lockdown restrictions and execute arbitrary code in the kernel. (CVE-2019-20908) It was discovered that the elf handling code in the Linux kernel did not initialize memory before using it in certain situations. A local attacker could use this to possibly expose sensitive information (kernel memory). (CVE-2020-10732) It was discovered that the Linux kernel did not correctly apply Speculative Store Bypass Disable (SSBD) mitigations in certain situations. A local attacker could possibly use this to expose sensitive information. (CVE-2020-10766) It was discovered that the Linux kernel did not correctly apply Indirect Branch Predictor Barrier (IBPB) mitigations in certain situations. A local attacker could possibly use this to expose sensitive information. (CVE-2020-10767) It was discovered that the Linux kernel could incorrectly enable indirect branch speculation after it has been disabled for a process via a prctl() call. A local attacker could possibly use this to expose sensitive information. (CVE-2020-10768) Mauricio Faria de Oliveira discovered that the aufs implementation in the Linux kernel improperly managed inode reference counts in the vfsub_dentry_open() method. A local attacker could use this vulnerability to cause a denial of service. (CVE-2020-11935) It was discovered that the Virtual Terminal keyboard driver in the Linux kernel contained an integer overflow. A local attacker could possibly use this to have a unspecified impact. (CVE-2020-13974) It was discovered that the efi subsystem in the Linux kernel did not handle memory allocation failures during early boot in some situations. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-12380) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 16.04 LTS: linux-image-4.4.0-1077-kvm 4.4.0-1077.84 linux-image-4.4.0-1111-aws 4.4.0-1111.123 linux-image-4.4.0-1136-raspi2 4.4.0-1136.145 linux-image-4.4.0-1140-snapdragon 4.4.0-1140.148 linux-image-4.4.0-186-generic 4.4.0-186.216 linux-image-4.4.0-186-generic-lpae 4.4.0-186.216 linux-image-4.4.0-186-lowlatency 4.4.0-186.216 linux-image-4.4.0-186-powerpc-e500mc 4.4.0-186.216 linux-image-4.4.0-186-powerpc-smp 4.4.0-186.216 linux-image-4.4.0-186-powerpc64-emb 4.4.0-186.216 linux-image-4.4.0-186-powerpc64-smp 4.4.0-186.216 linux-image-aws 4.4.0.1111.116 linux-image-generic 4.4.0.186.192 linux-image-generic-lpae 4.4.0.186.192 linux-image-kvm 4.4.0.1077.75 linux-image-lowlatency 4.4.0.186.192 linux-image-powerpc-e500mc 4.4.0.186.192 linux-image-powerpc-smp 4.4.0.186.192 linux-image-powerpc64-emb 4.4.0.186.192 linux-image-powerpc64-smp 4.4.0.186.192 linux-image-raspi2 4.4.0.1136.136 linux-image-snapdragon 4.4.0.1140.132 linux-image-virtual 4.4.0.186.192 Ubuntu 14.04 ESM: linux-image-4.4.0-1075-aws 4.4.0-1075.79 linux-image-4.4.0-186-generic 4.4.0-186.216~14.04.1 linux-image-4.4.0-186-generic-lpae 4.4.0-186.216~14.04.1 linux-image-4.4.0-186-lowlatency 4.4.0-186.216~14.04.1 linux-image-4.4.0-186-powerpc-e500mc 4.4.0-186.216~14.04.1 linux-image-4.4.0-186-powerpc-smp 4.4.0-186.216~14.04.1 linux-image-4.4.0-186-powerpc64-emb 4.4.0-186.216~14.04.1 linux-image-4.4.0-186-powerpc64-smp 4.4.0-186.216~14.04.1 linux-image-aws 4.4.0.1075.72 linux-image-generic-lpae-lts-xenial 4.4.0.186.163 linux-image-generic-lts-xenial 4.4.0.186.163 linux-image-lowlatency-lts-xenial 4.4.0.186.163 linux-image-powerpc-e500mc-lts-xenial 4.4.0.186.163 linux-image-powerpc-smp-lts-xenial 4.4.0.186.163 linux-image-powerpc64-emb-lts-xenial 4.4.0.186.163 linux-image-powerpc64-smp-lts-xenial 4.4.0.186.163 linux-image-virtual-lts-xenial 4.4.0.186.163 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/4427-1 CVE-2019-12380, CVE-2019-19947, CVE-2019-20810, CVE-2019-20908, CVE-2020-10732, CVE-2020-10766, CVE-2020-10767, CVE-2020-10768, CVE-2020-11935, CVE-2020-13974 Package Information: https://launchpad.net/ubuntu/+source/linux/4.4.0-186.216 https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1111.123 https://launchpad.net/ubuntu/+source/linux-kvm/4.4.0-1077.84 https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1136.145 https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1140.148