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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2018.3750.2 Linux kernel vulnerabilities 5 December 2018 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: linux linux-gcp linux-kvm linux-raspi2 Publisher: Ubuntu Operating System: Ubuntu Impact/Access: Access Confidential Data -- Existing Account Unauthorised Access -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2018-18955 CVE-2018-18653 CVE-2018-18445 CVE-2018-18281 CVE-2018-17972 CVE-2018-6559 Reference: ESB-2018.3737 Original Bulletin: http://www.ubuntu.com/usn/usn-3835-1 http://www.ubuntu.com/usn/usn-3836-1 http://www.ubuntu.com/usn/usn-3836-2 Comment: This bulletin contains three (3) Ubuntu security advisories. Revision History: December 5 2018: Added USN-3836-2 December 4 2018: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- ========================================================================== Ubuntu Security Notice USN-3835-1 December 03, 2018 linux, linux-gcp, linux-kvm, linux-raspi2 vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - - Ubuntu 18.10 Summary: Several security issues were fixed in the Linux kernel. Software Description: - - linux: Linux kernel - - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - - linux-kvm: Linux kernel for cloud environments - - linux-raspi2: Linux kernel for Raspberry Pi 2 Details: Jann Horn discovered that the procfs file system implementation in the Linux kernel did not properly restrict the ability to inspect the kernel stack of an arbitrary task. A local attacker could use this to expose sensitive information. (CVE-2018-17972) Jann Horn discovered that the mremap() system call in the Linux kernel did not properly flush the TLB when completing, potentially leaving access to a physical page after it has been released to the page allocator. A local attacker could use this to cause a denial of service (system crash), expose sensitive information, or possibly execute arbitrary code. (CVE-2018-18281) It was discovered that the BPF verifier in the Linux kernel did not correctly compute numeric bounds in some situations. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-18445) Daniel Dadap discovered that the module loading implementation in the Linux kernel did not properly enforce signed module loading when booted with UEFI Secure Boot in some situations. A local privileged attacker could use this to execute untrusted code in the kernel. (CVE-2018-18653) Jann Horn discovered that the Linux kernel mishandles mapping UID or GID ranges inside nested user namespaces in some situations. A local attacker could use this to bypass access controls on resources outside the namespace. (CVE-2018-18955) Philipp Wendler discovered that the overlayfs implementation in the Linux kernel did not properly verify the directory contents permissions from within a unprivileged user namespace. A local attacker could use this to expose sensitive information (protected file names). (CVE-2018-6559) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 18.10: linux-image-4.18.0-1004-gcp 4.18.0-1004.5 linux-image-4.18.0-1005-kvm 4.18.0-1005.5 linux-image-4.18.0-1007-raspi2 4.18.0-1007.9 linux-image-4.18.0-12-generic 4.18.0-12.13 linux-image-4.18.0-12-generic-lpae 4.18.0-12.13 linux-image-4.18.0-12-lowlatency 4.18.0-12.13 linux-image-4.18.0-12-snapdragon 4.18.0-12.13 linux-image-gcp 4.18.0.1004.4 linux-image-generic 4.18.0.12.13 linux-image-generic-lpae 4.18.0.12.13 linux-image-gke 4.18.0.1004.4 linux-image-kvm 4.18.0.1005.5 linux-image-lowlatency 4.18.0.12.13 linux-image-raspi2 4.18.0.1007.4 linux-image-snapdragon 4.18.0.12.13 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/usn/usn-3835-1 CVE-2018-17972, CVE-2018-18281, CVE-2018-18445, CVE-2018-18653, CVE-2018-18955, CVE-2018-6559 Package Information: https://launchpad.net/ubuntu/+source/linux/4.18.0-12.13 https://launchpad.net/ubuntu/+source/linux-gcp/4.18.0-1004.5 https://launchpad.net/ubuntu/+source/linux-kvm/4.18.0-1005.5 https://launchpad.net/ubuntu/+source/linux-raspi2/4.18.0-1007.9 - -------------------------------------------------------------------------------- ========================================================================== Ubuntu Security Notice USN-3836-1 December 03, 2018 linux, linux-gcp, linux-kvm, linux-raspi2 vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - - Ubuntu 18.04 LTS Summary: Several security issues were fixed in the Linux kernel. Software Description: - - linux: Linux kernel - - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - - linux-kvm: Linux kernel for cloud environments - - linux-raspi2: Linux kernel for Raspberry Pi 2 Details: Jann Horn discovered that the Linux kernel mishandles mapping UID or GID ranges inside nested user namespaces in some situations. A local attacker could use this to bypass access controls on resources outside the namespace. (CVE-2018-18955) Philipp Wendler discovered that the overlayfs implementation in the Linux kernel did not properly verify the directory contents permissions from within a unprivileged user namespace. A local attacker could use this to expose sensitive information (protected file names). (CVE-2018-6559) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 18.04 LTS: linux-image-4.15.0-1025-gcp 4.15.0-1025.26 linux-image-4.15.0-1027-kvm 4.15.0-1027.27 linux-image-4.15.0-1029-raspi2 4.15.0-1029.31 linux-image-4.15.0-42-generic 4.15.0-42.45 linux-image-4.15.0-42-generic-lpae 4.15.0-42.45 linux-image-4.15.0-42-lowlatency 4.15.0-42.45 linux-image-4.15.0-42-snapdragon 4.15.0-42.45 linux-image-gcp 4.15.0.1025.27 linux-image-generic 4.15.0.42.44 linux-image-generic-lpae 4.15.0.42.44 linux-image-gke 4.15.0.1025.27 linux-image-kvm 4.15.0.1027.27 linux-image-lowlatency 4.15.0.42.44 linux-image-raspi2 4.15.0.1029.27 linux-image-snapdragon 4.15.0.42.44 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/usn/usn-3836-1 CVE-2018-18955, CVE-2018-6559 Package Information: https://launchpad.net/ubuntu/+source/linux/4.15.0-42.45 https://launchpad.net/ubuntu/+source/linux-gcp/4.15.0-1025.26 https://launchpad.net/ubuntu/+source/linux-kvm/4.15.0-1027.27 https://launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1029.31 - -------------------------------------------------------------------------------- ========================================================================== Ubuntu Security Notice USN-3836-2 December 04, 2018 linux-hwe, linux-gcp vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - - Ubuntu 16.04 LTS Summary: Several security issues were fixed in the Linux kernel. Software Description: - - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - - linux-hwe: Linux hardware enablement (HWE) kernel Details: USN-3836-1 fixed vulnerabilities in the Linux kernel for Ubuntu 18.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 18.04 LTS for Ubuntu 16.04 LTS. Jann Horn discovered that the Linux kernel mishandles mapping UID or GID ranges inside nested user namespaces in some situations. A local attacker could use this to bypass access controls on resources outside the namespace. (CVE-2018-18955) Philipp Wendler discovered that the overlayfs implementation in the Linux kernel did not properly verify the directory contents permissions from within a unprivileged user namespace. A local attacker could use this to expose sensitive information (protected file names). (CVE-2018-6559) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 16.04 LTS: linux-image-4.15.0-1025-gcp 4.15.0-1025.26~16.04.1 linux-image-4.15.0-42-generic 4.15.0-42.45~16.04.1 linux-image-4.15.0-42-generic-lpae 4.15.0-42.45~16.04.1 linux-image-4.15.0-42-lowlatency 4.15.0-42.45~16.04.1 linux-image-gcp 4.15.0.1025.39 linux-image-generic-hwe-16.04 4.15.0.42.63 linux-image-generic-lpae-hwe-16.04 4.15.0.42.63 linux-image-gke 4.15.0.1025.39 linux-image-lowlatency-hwe-16.04 4.15.0.42.63 linux-image-oem 4.15.0.42.63 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: https://usn.ubuntu.com/usn/usn-3836-2 https://usn.ubuntu.com/usn/usn-3836-1 CVE-2018-18955, CVE-2018-6559 Package Information: https://launchpad.net/ubuntu/+source/linux-gcp/4.15.0-1025.26~16.04.1 https://launchpad.net/ubuntu/+source/linux-hwe/4.15.0-42.45~16.04.1 - --------------------------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 iQIVAwUBXAdiqmaOgq3Tt24GAQiZGw//RlRt7FM1d6WxeEOyKFnbV5j3NgWI2IHS uSRy1iE933TChnww7OzxCGt4niZbRr5M0VJb1PnM9eX37/2jzSSB/k+v2K987fwQ bFbOolwWpDVmg6CY7QV8NwFPHhLtK5fdwOEXBEycobayV8szaufHR3Sr9UUKmIK9 pELugRbcwLjDgUZ61nE5zCAm4qjD+cV8k+StEYAV3+GrEJWgX3jOCG0X7xcg1C6A iNs/sB1zE0V60RPAtFoD3EFovdj7NXcQpLMlmJ78KnLU580LkUepw81aPANVkdD3 viFQZ0jw1m+5aipHc5V20JIQDY+rsKzON8B2Sbwyd2i2uqhC/O7EZwuhPCh2H0lg NbqBf3kr9I1p7DqkkloJ5ydoBKeC2JSZEtvknfNM6Kq9rMGvglvRrW7MGxj+zhs2 IHQWY8+hAvdWo30xG56ueK4ZDetlCoQfbEbjHAuMXH09NhsiBsfqITjM7o2gEvLX k8MSPZGgLdPXPfWavmDgoSLCqhGY1OnIWL4rnWibC+81d90kp3hy7z6W8LFRJCz9 UzjR6eLwlG5HpX9++i94wRSHXbJvW24oVBJgVMaVDJC1Eu4zo5FxZZgDyQydcHVA SqWXyPr//jpeYidkC0T/f1JQCRgfUu9rjf0WPIh5xlgfxWChnCs5cefdoW5OLlFb BV/gkIx6WeI= =A/15 -----END PGP SIGNATURE-----