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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2019.4274 USN-4183: Linux kernel vulnerabilities 14 November 2019 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: linux kernel Publisher: Ubuntu Operating System: Ubuntu Impact/Access: Root Compromise -- Existing Account Access Privileged Data -- Existing Account Denial of Service -- Existing Account Unauthorised Access -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2019-17666 CVE-2019-16746 CVE-2019-15793 CVE-2019-15792 CVE-2019-15791 CVE-2019-11135 CVE-2019-0155 CVE-2019-0154 CVE-2018-12207 Reference: ASB-2019.0330 ASB-2019.0321 ASB-2019.0313 ESB-2019.4252 ESB-2019.4246 Original Bulletin: https://usn.ubuntu.com/4183-1/ https://usn.ubuntu.com/4183-2/ - --------------------------BEGIN INCLUDED TEXT-------------------- USN-4183-1: Linux kernel vulnerabilities 13 November 2019 linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oracle, linux-raspi2 vulnerabilities A security issue affects these releases of Ubuntu and its derivatives: o Ubuntu 19.10 Summary Several security issues were fixed in the Linux kernel. Software Description o linux - Linux kernel o linux-aws - Linux kernel for Amazon Web Services (AWS) systems o linux-azure - Linux kernel for Microsoft Azure Cloud systems o linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems o linux-kvm - Linux kernel for cloud environments o linux-oracle - Linux kernel for Oracle Cloud systems o linux-raspi2 - Linux kernel for Raspberry Pi 2 Details Stephan van Schaik, Alyssa Milburn, Sebastian A sterlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135) It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155) Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207) It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154) Jann Horn discovered a reference count underflow in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15791) Jann Horn discovered a type confusion vulnerability in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15792) Jann Horn discovered that the shiftfs implementation in the Linux kernel did not use the correct file system uid/gid when the user namespace of a lower file system is not in the init user namespace. A local attacker could use this to possibly bypass DAC permissions or have some other unspecified impact. (CVE-2019-15793) It was discovered that a buffer overflow existed in the 802.11 Wi-Fi configuration interface for the Linux kernel when handling beacon settings. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-16746) Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666) Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu 19.10 linux-image-5.3.0-1006-oracle - 5.3.0-1006.7 linux-image-5.3.0-1007-aws - 5.3.0-1007.8 linux-image-5.3.0-1007-azure - 5.3.0-1007.8 linux-image-5.3.0-1007-kvm - 5.3.0-1007.8 linux-image-5.3.0-1008-gcp - 5.3.0-1008.9 linux-image-5.3.0-1012-raspi2 - 5.3.0-1012.14 linux-image-5.3.0-22-generic - 5.3.0-22.24 linux-image-5.3.0-22-generic-lpae - 5.3.0-22.24 linux-image-5.3.0-22-lowlatency - 5.3.0-22.24 linux-image-5.3.0-22-snapdragon - 5.3.0-22.24 linux-image-aws - 5.3.0.1007.9 linux-image-azure - 5.3.0.1007.25 linux-image-gcp - 5.3.0.1008.9 linux-image-generic - 5.3.0.22.26 linux-image-generic-lpae - 5.3.0.22.26 linux-image-gke - 5.3.0.1008.9 linux-image-kvm - 5.3.0.1007.9 linux-image-lowlatency - 5.3.0.22.26 linux-image-oracle - 5.3.0.1006.7 linux-image-raspi2 - 5.3.0.1012.9 linux-image-snapdragon - 5.3.0.22.26 linux-image-virtual - 5.3.0.22.26 To update your system, please follow these instructions: https:// wiki.ubuntu.com/Security/Upgrades . Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively. 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-2018-12207 o CVE-2019-0154 o CVE-2019-0155 o CVE-2019-11135 o CVE-2019-15791 o CVE-2019-15792 o CVE-2019-15793 o CVE-2019-16746 o CVE-2019-17666 o https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/TAA_MCEPSC_i915 ============================================================================= USN-4183-2: Linux kernel vulnerability 13 November 2019 linux vulnerability A security issue affects these releases of Ubuntu and its derivatives: o Ubuntu 19.10 Summary Several security issues were fixed in the Linux kernel. Software Description o linux - Linux kernel Details USN-4183-1 fixed vulnerabilities in the Linux kernel. It was discovered that the kernel fix for CVE-2019-0155 (i915 missing Blitter Command Streamer check) was incomplete on 64-bit Intel x86 systems. This update addresses the issue. We apologize for the inconvenience. Original advisory details: Stephan van Schaik, Alyssa Milburn, Sebastian A sterlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135) It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155) Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207) It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154) Jann Horn discovered a reference count underflow in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15791) Jann Horn discovered a type confusion vulnerability in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15792) Jann Horn discovered that the shiftfs implementation in the Linux kernel did not use the correct file system uid/gid when the user namespace of a lower file system is not in the init user namespace. A local attacker could use this to possibly bypass DAC permissions or have some other unspecified impact. (CVE-2019-15793) It was discovered that a buffer overflow existed in the 802.11 Wi-Fi configuration interface for the Linux kernel when handling beacon settings. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-16746) Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666) Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu 19.10 linux-image-5.3.0-23-generic - 5.3.0-23.25 linux-image-5.3.0-23-generic-lpae - 5.3.0-23.25 linux-image-5.3.0-23-lowlatency - 5.3.0-23.25 linux-image-5.3.0-23-snapdragon - 5.3.0-23.25 linux-image-generic - 5.3.0.23.27 linux-image-generic-lpae - 5.3.0.23.27 linux-image-lowlatency - 5.3.0.23.27 linux-image-snapdragon - 5.3.0.23.27 linux-image-virtual - 5.3.0.23.27 To update your system, please follow these instructions: https:// wiki.ubuntu.com/Security/Upgrades . Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively. 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 USN-4183-1 o CVE-2019-0155 o LP: 1852141 - --------------------------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. 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If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBXczITmaOgq3Tt24GAQgdjA/9EEkuFNObQkNTV2sWRnWA8PaLiHzAXQij bNq8J0g7KVigkrnaqKUfRJzZN/6TOJOqyeNX6tGINKV+fW3d9hoC9PTUqo9aYm7y EnqUU6KL5CRbb6T8+lO9zvRKY0vR2ndwQijFdhy5urUrLOQZYn/sBlJmzxG255Z1 CO+hmUqCJ1RhrloeULfz/KNex+6f5m76AyzulRthH8/kyjxYOG2Mc+U6/CyrwojE FUK6WfEEdc7byle6PxtIrhIUMS72qvzJPhwTqb8V8LmRII2ISzO5XlbgX/yXkUdD NA4VOiHSSWsmLwtIpwKGBrnEjcO4282MOIdut8lCv4jK9dyxcpxi/nKfyYAZmDw5 Xm3YDkJFLBfA3LvyvDbOzJDQ28MvkR27B/8ikn0+3F+w6C3xlf3pjoRu/KHd8TnJ mCChIykqT5JtBOTdmwmj+JSNBmoqGtftxAOtZfm2mYDoNtRny9Yv53PcnGtLg9SU aVkaxNsWPYtlbJFKxN+/qcuPleTpNCKHTj/zK79CwQIuZY7bJWm2zvLQJoAQi/bJ NM0MR8kgoEO3AG6IPeQz3blTYN7bn/wjRJHtxPUipr0ANaiATXNdjg9uO8cW/OM7 ugsEfMa1tndbuxQZSeHK6H6aN7T7J8aKeKtRrtXpYVtBqBB7vAnWfX9FscJiIZXb NclXUCtWVbI= =vZwA -----END PGP SIGNATURE-----