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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2020.2562.2 USN-4439-1: Linux kernel vulnerabilities 31 July 2020 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: kernel Publisher: Ubuntu Operating System: Ubuntu Impact/Access: Root Compromise -- Existing Account Access Privileged Data -- Existing Account Denial of Service -- Remote/Unauthenticated Reduced Security -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2020-15780 CVE-2020-13974 CVE-2020-11935 CVE-2020-10768 CVE-2020-10767 CVE-2020-10766 CVE-2020-10757 CVE-2020-10732 CVE-2019-20908 CVE-2019-20810 CVE-2019-19462 CVE-2019-19036 CVE-2019-16089 CVE-2019-12380 Reference: ESB-2020.2532 ESB-2020.2507 ESB-2019.3913 ESB-2019.2593 Original Bulletin: https://usn.ubuntu.com/4439-1/ https://usn.ubuntu.com/4440-1/ Revision History: July 31 2020: USN-4440-1: Additional packages added July 28 2020: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- USN-4439-1: Linux kernel vulnerabilities 27 July 2020 Several security issues were fixed in the Linux kernel. Releases o Ubuntu 18.04 LTS Packages o linux-gke-5.0 - Linux kernel for Google Container Engine (GKE) systems o linux-oem-osp1 - Linux kernel for OEM systems Details It was discovered that the network block device (nbd) implementation in the Linux kernel did not properly check for error conditions in some situations. An attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-16089) It was discovered that the btrfs file system implementation in the Linux kernel did not properly validate file system metadata in some situations. An attacker could use this to construct a malicious btrfs image that, when mounted, could cause a denial of service (system crash). (CVE-2019-19036) It was discovered that the kernel->user space relay implementation in the Linux kernel did not properly check return values in some situations. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-19462) 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) 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) Fan Yang discovered that the mremap implementation in the Linux kernel did not properly handle DAX Huge Pages. A local attacker with access to DAX storage could use this to gain administrative privileges. (CVE-2020-10757) 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 an 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) 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) Jason A. Donenfeld discovered that the ACPI implementation in the Linux kernel did not properly restrict loading ACPI tables via configfs. A privileged attacker could use this to bypass Secure Boot lockdown restrictions and execute arbitrary code in the kernel. (CVE-2020-15780) Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu 18.04 o linux-image-5.0.0-1045-gke - 5.0.0-1045.46 o linux-image-5.0.0-1065-oem-osp1 - 5.0.0-1065.70 o linux-image-gke-5.0 - 5.0.0.1045.30 o linux-image-oem-osp1 - 5.0.0.1065.63 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 o CVE-2019-12380 o CVE-2019-16089 o CVE-2019-19036 o CVE-2019-19462 o CVE-2019-20810 o CVE-2020-10732 o CVE-2020-10757 o CVE-2020-10766 o CVE-2020-10767 o CVE-2020-10768 o CVE-2020-11935 o CVE-2020-13974 o CVE-2020-15780 o CVE-2019-20908 - -------------------------------------------------------------------------------- USN-4440-1: linux kernel vulnerabilities 31 July 2020 Several security issues were fixed in the Linux kernel. Releases o Ubuntu 18.04 LTS Packages o linux-aws-5.3 - Linux kernel for Amazon Web Services (AWS) systems o linux-azure-5.3 - Linux kernel for microsoft azure cloud systems o linux-gcp-5.3 - Linux kernel for Google Cloud Platform (GCP) systems o linux-gke-5.3 - Linux kernel for Google Container Engine (GKE) systems o linux-hwe - Linux hardware enablement (HWE) kernel o linux-oracle-5.3 - Linux kernel for Oracle Cloud systems o linux-raspi2-5.3 - Linux kernel for Raspberry Pi (V7) systems Details It was discovered that the network block device (nbd) implementation in the Linux kernel did not properly check for error conditions in some situations. An attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-16089) It was discovered that the kernel->user space relay implementation in the Linux kernel did not properly check return values in some situations. A local attacker could possibly use this to cause a denial of service (system crash). (CVE-2019-19462) 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) Fan Yang discovered that the mremap implementation in the Linux kernel did not properly handle DAX Huge Pages. A local attacker with access to DAX storage could use this to gain administrative privileges. (CVE-2020-10757) 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 an unspecified impact. (CVE-2020-13974) Jason A. Donenfeld discovered that the ACPI implementation in the Linux kernel did not properly restrict loading ACPI tables via configfs. A privileged attacker could use this to bypass Secure Boot lockdown restrictions and execute arbitrary code in the kernel. (CVE-2020-15780) Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu 18.04 o linux-image-5.3.0-1030-oracle - 5.3.0-1030.32~18.04.1 o linux-image-5.3.0-1030-raspi2 - 5.3.0-1030.32~18.04.2 o linux-image-5.3.0-1032-aws - 5.3.0-1032.34~18.04.2 o linux-image-5.3.0-1032-gcp - 5.3.0-1032.34~18.04.1 o linux-image-5.3.0-1032-gke - 5.3.0-1032.34~18.04.1 o linux-image-5.3.0-1034-azure - 5.3.0-1034.35~18.04.1 o linux-image-5.3.0-64-generic - 5.3.0-64.58~18.04.1 o linux-image-5.3.0-64-generic-lpae - 5.3.0-64.58~18.04.1 o linux-image-5.3.0-64-lowlatency - 5.3.0-64.58~18.04.1 o linux-image-aws - 5.3.0.1032.31 o linux-image-azure - 5.3.0.1034.30 o linux-image-gcp - 5.3.0.1032.26 o linux-image-gke-5.3 - 5.3.0.1032.17 o linux-image-gkeop-5.3 - 5.3.0.64.120 o linux-image-oracle - 5.3.0.1030.27 o linux-image-raspi2-hwe-18.04 - 5.3.0.1030.20 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 o CVE-2019-16089 o CVE-2019-19462 o CVE-2019-20810 o CVE-2019-20908 o CVE-2020-10732 o CVE-2020-10757 o CVE-2020-10766 o CVE-2020-10767 o CVE-2020-10768 o CVE-2020-11935 o CVE-2020-13974 o CVE-2020-15780 - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. 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On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBXyO/9+NLKJtyKPYoAQiMQw/9E8TiismVIzvdLOO0go2q3KldHpILOLQL 3niluLV3udiSW2vHjaXwX8b3zzQlJTcTLlXLcsxfrdVTwTQwcIc+D4gDDdYNDArC P86lYpvfbjljEIn7VIRowzZrbCYAqQTWRaKMtFj7UlmB/HTWfGeF2cTwm31AFKDX Emg2vlV77RwAuQwO+bhjgbIL6hRo7RhBzT9rJmoy7U1BtYS4dsg7C2h1X2spZwzR fqP0SD9ECOEzyabGd56sh7NN2AxmLZfb6qbzcMaq59jbBadBdAIv45hHiUA0g6AT moYP23w3Zm+Z6WvZd9F7azw1qPQsHUsv3K9YVABjoyO5otYdhQvWCrkvejvwRSj+ 4OOQZHJa2y4FPON+pOyggghlpeN5TwWp3v3AS4J7ep8N+37beAr2vu9S4sotlaWM nsLRTHLU7s+26u/xIAtEPUchuTZSDZI48y13iaAiMLY5/aregqfTAWSdDUhDkNuw jtXq1KhQFHs9WZC5eBHVxIB/r6JbGq8ebxIbik7LRAsCKp+opOkO+kpvcOaKiWpi mI4NuoU/dQ12qx9hsOEf+CuBwD3qHdWwSLEDAgjXmzyHPUq1qDjyiTiIlfhhx3sA Po/i0pZWXsOyREXOhItGvafB5YMyoIGsUPad7/ZgUCjyAfHSpvGG/YSCOVW/Fa9k TDhn2NieghM= =ZqL/ -----END PGP SIGNATURE-----