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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2020.3011.2 USN-4485-1: Linux kernel vulnerabilities 4 September 2020 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: kernel Publisher: Ubuntu Operating System: Ubuntu Impact/Access: Execute Arbitrary Code/Commands -- Existing Account Access Privileged Data -- Existing Account Denial of Service -- Existing Account Reduced Security -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2020-24394 CVE-2020-15393 CVE-2020-13974 CVE-2020-12771 CVE-2020-12656 CVE-2020-12655 CVE-2020-10781 CVE-2020-10768 CVE-2020-10767 CVE-2020-10766 CVE-2020-10732 CVE-2019-20810 CVE-2019-19947 CVE-2018-20669 Reference: ESB-2020.3008 ESB-2020.2907 ESB-2020.2864.2 ESB-2020.2842 Original Bulletin: https://usn.ubuntu.com/4485-1/ Revision History: September 4 2020: Vendor added new kernel version details September 2 2020: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- USN-4485-1: Linux kernel vulnerabilities 03 September 2020 Several security issues were fixed in the Linux kernel. Releases o Ubuntu 18.04 LTS o Ubuntu 16.04 LTS o Ubuntu 14.04 ESM Packages o linux - Linux kernel o linux-aws - Linux kernel for Amazon Web Services (AWS) systems o linux-aws-hwe - Linux kernel for Amazon Web Services (AWS-HWE) systems o linux-azure - Linux kernel for Microsoft Azure Cloud systems o linux-azure-4.15 - Linux kernel for Microsoft Azure Cloud systems o linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems o linux-gcp-4.15 - Linux kernel for Google Cloud Platform (GCP) systems o linux-gke-4.15 - Linux kernel for Google Container Engine (GKE) systems o linux-hwe - Linux hardware enablement (HWE) kernel o linux-kvm - Linux kernel for cloud environments o linux-oem - Linux kernel for OEM systems o linux-oracle - Linux kernel for Oracle Cloud systems o linux-raspi2 - Linux kernel for Raspberry Pi (V8) systems o linux-snapdragon - Linux kernel for Qualcomm Snapdragon processors Details Timothy Michaud discovered that the i915 graphics driver in the Linux kernel did not properly validate user memory locations for the i915_gem_execbuffer2_ioctl. A local attacker could possibly use this to cause a denial of service or execute arbitrary code. (CVE-2018-20669) 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) 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) Luca Bruno discovered that the zram module in the Linux kernel did not properly restrict unprivileged users from accessing the hot_add sysfs file. A local attacker could use this to cause a denial of service (memory exhaustion). (CVE-2020-10781) It was discovered that the XFS file system implementation in the Linux kernel did not properly validate meta data in some circumstances. An attacker could use this to construct a malicious XFS image that, when mounted, could cause a denial of service. (CVE-2020-12655) It was discovered that the bcache subsystem in the Linux kernel did not properly release a lock in some error conditions. A local attacker could possibly use this to cause a denial of service. (CVE-2020-12771) 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) Kyungtae Kim discovered that the USB testing driver in the Linux kernel did not properly deallocate memory on disconnect events. A physically proximate attacker could use this to cause a denial of service (memory exhaustion). (CVE-2020-15393) It was discovered that the NFS server implementation in the Linux kernel did not properly honor umask settings when setting permissions while creating file system objects if the underlying file system did not support ACLs. An attacker could possibly use this to expose sensitive information or violate system integrity. (CVE-2020-24394) It was discovered that the Kerberos SUNRPC GSS implementation in the Linux kernel did not properly deallocate memory on module unload. A local privileged attacker could possibly use this to cause a denial of service (memory exhaustion). (CVE-2020-12656) Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu 18.04 o linux-image-4.15.0-1051-oracle - 4.15.0-1051.55 o linux-image-4.15.0-1067-gke - 4.15.0-1067.70 o linux-image-4.15.0-1068-raspi2 - 4.15.0-1068.72 o linux-image-4.15.0-1072-kvm - 4.15.0-1072.73 o linux-image-4.15.0-1080-aws - 4.15.0-1080.84 o linux-image-4.15.0-1081-gcp - 4.15.0-1081.92 o linux-image-4.15.0-1084-snapdragon - 4.15.0-1084.92 o linux-image-4.15.0-1093-azure - 4.15.0-1093.103 o linux-image-4.15.0-1094-oem - 4.15.0-1094.104 o linux-image-4.15.0-115-generic - 4.15.0-115.116 o linux-image-4.15.0-115-generic-lpae - 4.15.0-115.116 o linux-image-4.15.0-115-lowlatency - 4.15.0-115.116 o linux-image-aws-lts-18.04 - 4.15.0.1080.82 o linux-image-azure-lts-18.04 - 4.15.0.1093.67 o linux-image-gcp-lts-18.04 - 4.15.0.1081.99 o linux-image-generic - 4.15.0.115.103 o linux-image-generic-lpae - 4.15.0.115.103 o linux-image-gke - 4.15.0.1067.71 o linux-image-gke-4.15 - 4.15.0.1067.71 o linux-image-kvm - 4.15.0.1072.68 o linux-image-lowlatency - 4.15.0.115.103 o linux-image-oem - 4.15.0.1094.98 o linux-image-oracle-lts-18.04 - 4.15.0.1051.62 o linux-image-powerpc-e500mc - 4.15.0.115.103 o linux-image-powerpc-smp - 4.15.0.115.103 o linux-image-powerpc64-emb - 4.15.0.115.103 o linux-image-powerpc64-smp - 4.15.0.115.103 o linux-image-raspi2 - 4.15.0.1068.66 o linux-image-snapdragon - 4.15.0.1084.87 o linux-image-virtual - 4.15.0.115.103 Ubuntu 16.04 o linux-image-4.15.0-1051-oracle - 4.15.0-1051.55~16.04.1 o linux-image-4.15.0-1080-aws - 4.15.0-1080.84~16.04.1 o linux-image-4.15.0-1081-gcp - 4.15.0-1081.92~16.04.1 o linux-image-4.15.0-1093-azure - 4.15.0-1093.103~16.04.1 o linux-image-4.15.0-115-generic - 4.15.0-115.116~16.04.1 o linux-image-4.15.0-115-generic-lpae - 4.15.0-115.116~16.04.1 o linux-image-4.15.0-115-lowlatency - 4.15.0-115.116~16.04.1 o linux-image-aws-hwe - 4.15.0.1080.77 o linux-image-azure - 4.15.0.1093.88 o linux-image-azure-edge - 4.15.0.1093.88 o linux-image-gcp - 4.15.0.1081.83 o linux-image-generic-hwe-16.04 - 4.15.0.115.116 o linux-image-generic-lpae-hwe-16.04 - 4.15.0.115.116 o linux-image-gke - 4.15.0.1081.83 o linux-image-lowlatency-hwe-16.04 - 4.15.0.115.116 o linux-image-oem - 4.15.0.115.116 o linux-image-oracle - 4.15.0.1051.42 o linux-image-virtual-hwe-16.04 - 4.15.0.115.116 Ubuntu 14.04 o linux-image-4.15.0-1093-azure - 4.15.0-1093.103~14.04.1 o linux-image-azure - 4.15.0.1093.70 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-2018-20669 o CVE-2019-19947 o CVE-2019-20810 o CVE-2020-10732 o CVE-2020-10766 o CVE-2020-10767 o CVE-2020-10768 o CVE-2020-10781 o CVE-2020-12655 o CVE-2020-12656 o CVE-2020-12771 o CVE-2020-13974 o CVE-2020-15393 o CVE-2020-24394 - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. 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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 iQIVAwUBX1GuweNLKJtyKPYoAQgtlg//SHASq8L2AsDiPeNigBCNR3290bq9HFvk jJGQ0aueieZRylPs/DOuh1O3f/lpbMXMKJSKGaLBu9JdiJjjSdN6TdSaqetcaNYs EprXyuzTpsBaD1HT3PZwsWA+SwFkOWJ9j0fw1TuTEQEsG9i6YYOBdONW/WNQQB7x xLKd9SBA3KacNIsFmofWMEv3TLOejJOSIJAQPt2SK57F25ClY3kSWj7dpctGJXnr R/ZKib7I4azuPlu5GVieItZ+nnMN5d4R8AAZED7IUILB/g4rZGQ9tcOmrekdqcTO szN2tuXzgkg28ENWeBNoJ+o3ElDGD8WkrcRrUYakDMBmjXLnIoZ8XyriPcehM51k kl//LfI1JpReY9HdSDTS6J7J4DcGGkKlyl6IaBHk9CrhKi1dzQibb3yWIuoUGRHe VX/5Xox7Auj2VGF3Snig1ZJm+kIcOVopvfDB7coXi8p3m/CxLDNkNwUHqEBjL9qm rmEX2UrukuGE3/Pq2L+QnxiPtZaQ9hLPdG1m+3l4buCLNIa0eG1uWpqbaNc2TVFu 7/b1Z2H8y/LHM+TxAlEMW5ukBzGTOjp6xf0A2NBkDeZ1qJmffXNS5Q+b8kilMWWn LtZmGnhPRVuk6PiG92j+BZiTrudWdZ6/NZQLNzfaLQ3SQt5ASww+0/cUydEzlmRT yUiRG3ARyqk= =Huz3 -----END PGP SIGNATURE-----