[USN-5018-1] Linux kernel vulnerabilities

========================================================================== Ubuntu Security Notice USN-5018-1 July 20, 2021
linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-gcp, linux-gcp-4.15, linux-hwe, linux-kvm, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities ==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 18.04 LTS – Ubuntu 16.04 ESM – Ubuntu 14.04 ESM
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-4.15: Linux kernel for Microsoft Azure Cloud systems – linux-gcp-4.15: Linux kernel for Google Cloud Platform (GCP) systems – linux-kvm: Linux kernel for cloud environments – linux-oracle: Linux kernel for Oracle Cloud systems – linux-raspi2: Linux kernel for Raspberry Pi (V8) systems – linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors – linux-aws-hwe: Linux kernel for Amazon Web Services (AWS-HWE) systems – linux-azure: Linux kernel for Microsoft Azure Cloud systems – linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems – linux-hwe: Linux hardware enablement (HWE) kernel
Details:
It was discovered that the virtual file system implementation in the Linux kernel contained an unsigned to signed integer conversion error. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-33909)
Piotr Krysiuk discovered that the eBPF implementation in the Linux kernel did not 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 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 could reassemble mixed encrypted and plaintext fragments. A physically proximate attacker could possibly use this issue to inject packets or exfiltrate selected fragments. (CVE-2020-26147)
It was discovered that the bluetooth subsystem in the Linux kernel did not properly perform access control. An authenticated attacker could possibly use this to expose sensitive information. (CVE-2020-26558, CVE-2021-0129)
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 could 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)
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 18.04 LTS: linux-image-4.15.0-1078-oracle 4.15.0-1078.86 linux-image-4.15.0-1092-raspi2 4.15.0-1092.98 linux-image-4.15.0-1097-kvm 4.15.0-1097.99 linux-image-4.15.0-1106-gcp 4.15.0-1106.120 linux-image-4.15.0-1109-aws 4.15.0-1109.116 linux-image-4.15.0-1109-snapdragon 4.15.0-1109.118 linux-image-4.15.0-1121-azure 4.15.0-1121.134 linux-image-4.15.0-151-generic 4.15.0-151.157 linux-image-4.15.0-151-generic-lpae 4.15.0-151.157 linux-image-4.15.0-151-lowlatency 4.15.0-151.157 linux-image-aws-lts-18.04 4.15.0.1109.112 linux-image-azure-lts-18.04 4.15.0.1121.94 linux-image-gcp-lts-18.04 4.15.0.1106.125 linux-image-generic 4.15.0.151.139 linux-image-generic-lpae 4.15.0.151.139 linux-image-kvm 4.15.0.1097.93 linux-image-lowlatency 4.15.0.151.139 linux-image-oracle-lts-18.04 4.15.0.1078.88 linux-image-raspi2 4.15.0.1092.90 linux-image-snapdragon 4.15.0.1109.112 linux-image-virtual 4.15.0.151.139
Ubuntu 16.04 ESM: linux-image-4.15.0-1078-oracle 4.15.0-1078.86~16.04.1 linux-image-4.15.0-1106-gcp 4.15.0-1106.120~16.04.1 linux-image-4.15.0-1109-aws 4.15.0-1109.116~16.04.1 linux-image-4.15.0-1121-azure 4.15.0-1121.134~16.04.1 linux-image-4.15.0-151-generic 4.15.0-151.157~16.04.1 linux-image-4.15.0-151-lowlatency 4.15.0-151.157~16.04.1 linux-image-aws-hwe 4.15.0.1109.100 linux-image-azure 4.15.0.1121.112 linux-image-gcp 4.15.0.1106.107 linux-image-generic-hwe-16.04 4.15.0.151.146 linux-image-gke 4.15.0.1106.107 linux-image-lowlatency-hwe-16.04 4.15.0.151.146 linux-image-oem 4.15.0.151.146 linux-image-oracle 4.15.0.1078.66 linux-image-virtual-hwe-16.04 4.15.0.151.146
Ubuntu 14.04 ESM: linux-image-4.15.0-1121-azure 4.15.0-1121.134~14.04.1 linux-image-azure 4.15.0.1121.94
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: ubuntu.com/security/notices/USN-5018-1 CVE-2020-24586, CVE-2020-24587, CVE-2020-26139, CVE-2020-26147, CVE-2020-26558, CVE-2021-0129, CVE-2021-23134, CVE-2021-31829, CVE-2021-32399, CVE-2021-33034, CVE-2021-33200, CVE-2021-33909
Package Information: launchpad.net/ubuntu/+source/linux/4.15.0-151.157 launchpad.net/ubuntu/+source/linux-aws/4.15.0-1109.116 launchpad.net/ubuntu/+source/linux-azure-4.15/4.15.0-1121.134 launchpad.net/ubuntu/+source/linux-gcp-4.15/4.15.0-1106.120 launchpad.net/ubuntu/+source/linux-kvm/4.15.0-1097.99 launchpad.net/ubuntu/+source/linux-oracle/4.15.0-1078.86 launchpad.net/ubuntu/+source/linux-raspi2/4.15.0-1092.98 launchpad.net/ubuntu/+source/linux-snapdragon/4.15.0-1109.118