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Ubuntu 20.04 LTS USN-5000-1 Critical: Linux Kernel DoS Risks

Several security issues were fixed in the Linux kernel.. =========================================================================Ubuntu Security Notice USN-5000-1 June 23, 2021 linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp, linux-gcp-5.4, linux-gke, linux-gke-5.4, linux-gkeop, linux-gkeop-5.4, linux-hwe-5.4, linux-oracle, linux-oracle-5.4, linux-raspi, linux-raspi-5.4 vulnerabilities ========================================================================= A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 20.04 LTS - Ubuntu 18.04 LTS 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-azure: Linux kernel for Microsoft Azure Cloud systems - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems - linux-gke: Linux kernel for Google Container Engine (GKE) systems - linux-gkeop: Linux kernel for Google Container Engine (GKE) systems - linux-oracle: Linux kernel for Oracle Cloud systems - linux-raspi: Linux kernel for Raspberry Pi (V8) systems - linux-aws-5.4: Linux kernel for Amazon Web Services (AWS) systems - linux-azure-5.4: Linux kernel for Microsoft Azure cloud systems - linux-gcp-5.4: Linux kernel for Google Cloud Platform (GCP) systems - linux-gke-5.4: Linux kernel for Google Container Engine (GKE) systems - linux-gkeop-5.4: Linux kernel for Google Container Engine (GKE) systems - linux-hwe-5.4: Linux hardware enablement (HWE) kernel - linux-oracle-5.4: Linux kernel for Oracle Cloud systems - linux-raspi-5.4: Linux kernel for Raspberry Pi (V8) systems Details: Norbert Slusarek discovered a race condition in the CAN BCM networking protocol of the Linux kernel leading to multiple use-after-free vulnerabilities. A local attacker could use this issue to execute arbitrary code. (CVE-2021-3609) Piotr Krysiuk discovered that the eBPF implementation in the Linux kernel didnot properly enforce limits for pointer operations. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-33200) Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation did not properly clear received fragments from memory in some situations. A physically proximate attacker could possibly use this issue to inject packets or expose sensitive information. (CVE-2020-24586) Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation incorrectly handled encrypted fragments. A physically proximate attacker could possibly use this issue to decrypt fragments. (CVE-2020-24587) Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation incorrectly handled certain malformed frames. If a user were tricked into connecting to a malicious server, a physically proximate attacker could use this issue to inject packets. (CVE-2020-24588) Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation incorrectly handled EAPOL frames from unauthenticated senders. A physically proximate attacker could inject malicious packets to cause a denial of service (system crash). (CVE-2020-26139) Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation did not properly verify certain fragmented frames. A physically proximate attacker could possibly use this issue to inject or decrypt packets. (CVE-2020-26141) Mathy Vanhoef discovered that the in the Linux kernel’s WiFi implementation leading to accepting plaintext fragments. A physically proximate attacker could use this issue to inject packets. (CVE-2020-26145) Mathy Vanhoef discovered that the the Linux kernel’s WiFi implementation leading to reassembling mixed encrypted and plaintext fragments. A physically proximate attacker could possibly use this issue to inject packets or exfiltrate selected fragments. (CVE-2020-26147) Or Cohen discovered that the SCTP implementation in the Linux kernel contained a racecondition in some situations, leading to a use-after-free condition. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-23133) Or Cohen and Nadav Markus discovered a use-after-free vulnerability in the nfc implementation in the Linux kernel. A privileged local attacker could use this issue to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-23134) Piotr Krysiuk discovered that the eBPF implementation in the Linux kernel did not properly prevent speculative loads in certain situations. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2021-31829) It was discovered that a race condition in the kernel Bluetooth subsystem can lead to use-after-free of slab objects. An attacker could use this issue to possibly execute arbitrary code. (CVE-2021-32399) It was discovered that a use-after-free existed in the Bluetooth HCI driver of the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-33034) It was discovered that an out-of-bounds (OOB) memory access flaw in the f2fs module of the Linux kernel. A local attacker could use this issue to cause a denial of service (system crash). (CVE-2021-3506) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 20.04 LTS: linux-image-5.4.0-1018-gkeop 5.4.0-1018.19 linux-image-5.4.0-1038-raspi 5.4.0-1038.41 linux-image-5.4.0-1046-gcp 5.4.0-1046.49 linux-image-5.4.0-1046-gke 5.4.0-1046.48 linux-image-5.4.0-1048-oracle 5.4.0-1048.52 linux-image-5.4.0-1051-aws 5.4.0-1051.53 linux-image-5.4.0-1051-azure 5.4.0-1051.53 linux-image-5.4.0-77-generic 5.4.0-77.86 linux-image-5.4.0-77-generic-lpae 5.4.0-77.86 linux-image-5.4.0-77-lowlatency 5.4.0-77.86 linux-image-aws-lts-20.04 5.4.0.1051.53 linux-image-azure-lts-20.04 5.4.0.1051.49 linux-image-gcp-lts-20.04 5.4.0.1046.55 linux-image-generic 5.4.0.77.80 linux-image-generic-lpae 5.4.0.77.80 linux-image-gke 5.4.0.1046.55 linux-image-gke-5.4 5.4.0.1046.55 linux-image-gkeop 5.4.0.1018.21 linux-image-gkeop-5.4 5.4.0.1018.21 linux-image-lowlatency 5.4.0.77.80 linux-image-oem 5.4.0.77.80 linux-image-oem-osp1 5.4.0.77.80 linux-image-oracle-lts-20.04 5.4.0.1048.48 linux-image-raspi 5.4.0.1038.73 linux-image-raspi2 5.4.0.1038.73 linux-image-virtual 5.4.0.77.80 Ubuntu 18.04 LTS: linux-image-5.4.0-1018-gkeop 5.4.0-1018.19~18.04.1 linux-image-5.4.0-1038-raspi 5.4.0-1038.41~18.04.1 linux-image-5.4.0-1046-gcp 5.4.0-1046.49~18.04.1 linux-image-5.4.0-1046-gke 5.4.0-1046.48~18.04.1 linux-image-5.4.0-1048-oracle 5.4.0-1048.52~18.04.1 linux-image-5.4.0-1051-aws 5.4.0-1051.53~18.04.1 linux-image-5.4.0-1051-azure 5.4.0-1051.53~18.04.1 linux-image-5.4.0-77-generic 5.4.0-77.86~18.04.1 linux-image-5.4.0-77-generic-lpae 5.4.0-77.86~18.04.1 linux-image-5.4.0-77-lowlatency 5.4.0-77.86~18.04.1 linux-image-aws 5.4.0.1051.33 linux-image-azure 5.4.0.1051.30 linux-image-gcp 5.4.0.1046.33 linux-image-generic-hwe-18.04 5.4.0.77.86~18.04.69 linux-image-generic-lpae-hwe-18.04 5.4.0.77.86~18.04.69 linux-image-gke-5.4 5.4.0.1046.48~18.04.12 linux-image-gkeop-5.4 5.4.0.1018.19~18.04.19 linux-image-lowlatency-hwe-18.04 5.4.0.77.86~18.04.69 linux-image-oem 5.4.0.77.86~18.04.69 linux-image-oem-osp1 5.4.0.77.86~18.04.69 linux-image-oracle 5.4.0.1048.52~18.04.30 linux-image-raspi-hwe-18.04 5.4.0.1038.40 linux-image-snapdragon-hwe-18.04 5.4.0.77.86~18.04.69 linux-image-virtual-hwe-18.04 5.4.0.77.86~18.04.69 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://ubuntu.com/security/notices/USN-5000-1 CVE-2020-24586, CVE-2020-24587, CVE-2020-24588, CVE-2020-26139, CVE-2020-26141, CVE-2020-26145, CVE-2020-26147, CVE-2021-23133, CVE-2021-23134, CVE-2021-31829, CVE-2021-32399, CVE-2021-33034, CVE-2021-33200, CVE-2021-3506, CVE-2021-3609 Package Information: https://launchpad.net/ubuntu/+source/linux/5.4.0-77.86 https://launchpad.net/ubuntu/+source/linux-aws/5.4.0-1051.53 https://launchpad.net/ubuntu/+source/linux-azure/5.4.0-1051.53 https://launchpad.net/ubuntu/+source/linux-gcp/5.4.0-1046.49 https://launchpad.net/ubuntu/+source/linux-gke/5.4.0-1046.48 https://launchpad.net/ubuntu/+source/linux-gkeop/5.4.0-1018.19 https://launchpad.net/ubuntu/+source/linux-oracle/5.4.0-1048.52 https://launchpad.net/ubuntu/+source/linux-raspi/5.4.0-1038.41 https://launchpad.net/ubuntu/+source/linux-aws-5.4/5.4.0-1051.53~18.04.1 https://launchpad.net/ubuntu/+source/linux-azure-5.4/5.4.0-1051.53~18.04.1 https://launchpad.net/ubuntu/+source/linux-gcp-5.4/5.4.0-1046.49~18.04.1 https://launchpad.net/ubuntu/+source/linux-gke-5.4/5.4.0-1046.48~18.04.1 https://launchpad.net/ubuntu/+source/linux-gkeop-5.4/5.4.0-1018.19~18.04.1 https://launchpad.net/ubuntu/+source/linux-hwe-5.4/5.4.0-77.86~18.04.1 https://launchpad.net/ubuntu/+source/linux-oracle-5.4/5.4.0-1048.52~18.04.1 https://launchpad.net/ubuntu/+source/linux-raspi-5.4/5.4.0-1038.41~18.04.1 . Major vulnerabilities addressed in the Linux kernel for Ubuntu are impacting cloud infrastructure and Wi-Fi encryption, particularly concerning potential denial of service threats.. Linux Kernel Issues, Ubuntu Cloud Updates, Kernel Security Risks, Denial Of Service, Cloud Vulnerabilities. . Severity: Critical. LinuxSecurity.com Team

Jun 23, 2021 •Critical Ubuntu