1. Ubuntu Security Notices
  2. USN-4878-1

USN-4878-1: Linux kernel vulnerabilities

Publication date

16 March 2021

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-aws-5.4 - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-azure-5.4 - Linux kernel for Microsoft Azure cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) 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 - 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-kvm - Linux kernel for cloud environments
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-oracle-5.4 - Linux kernel for Oracle Cloud systems
  • linux-raspi - Linux kernel for Raspberry Pi (V8) systems
  • linux-raspi-5.4 - Linux kernel for Raspberry Pi (V8) systems

Details

It was discovered that the Marvell WiFi-Ex device driver in the Linux
kernel did not properly validate ad-hoc SSIDs. A local attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2020-36158)

Ryota Shiga discovered that the sockopt BPF hooks in the Linux kernel could
allow a user space program to probe for valid kernel addresses. A local
attacker could use this to ease exploitation of another kernel
vulnerability. (CVE-2021-20239)

It was discovered that the priority inheritance futex implementation in the
Linux kernel contained a race condition, leading to a use-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2021-3347)

吴异 discovered that the NFS implementation...

It was discovered that the Marvell WiFi-Ex device driver in the Linux
kernel did not properly validate ad-hoc SSIDs. A local attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2020-36158)

Ryota Shiga discovered that the sockopt BPF hooks in the Linux kernel could
allow a user space program to probe for valid kernel addresses. A local
attacker could use this to ease exploitation of another kernel
vulnerability. (CVE-2021-20239)

It was discovered that the priority inheritance futex implementation in the
Linux kernel contained a race condition, leading to a use-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2021-3347)

吴异 discovered that the NFS implementation in the Linux kernel did not
properly prevent access outside of an NFS export that is a subdirectory of
a file system. An attacker could possibly use this to bypass NFS access
restrictions. (CVE-2021-3178)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
20.04 focal linux-image-5.4.0-1011-gkeop –  5.4.0-1011.12
linux-image-5.4.0-1030-raspi –  5.4.0-1030.33
linux-image-5.4.0-1034-kvm –  5.4.0-1034.35
linux-image-5.4.0-1038-gcp –  5.4.0-1038.41
linux-image-5.4.0-1039-aws –  5.4.0-1039.41
linux-image-5.4.0-1039-oracle –  5.4.0-1039.42
linux-image-5.4.0-1041-azure –  5.4.0-1041.43
linux-image-5.4.0-67-generic –  5.4.0-67.75
linux-image-5.4.0-67-generic-lpae –  5.4.0-67.75
linux-image-5.4.0-67-lowlatency –  5.4.0-67.75
linux-image-aws –  5.4.0.1039.40
linux-image-azure –  5.4.0.1041.39
linux-image-gcp –  5.4.0.1038.47
linux-image-generic –  5.4.0.67.70
linux-image-generic-lpae –  5.4.0.67.70
linux-image-gkeop –  5.4.0.1011.14
linux-image-gkeop-5.4 –  5.4.0.1011.14
linux-image-kvm –  5.4.0.1034.32
linux-image-lowlatency –  5.4.0.67.70
linux-image-oem –  5.4.0.67.70
linux-image-oem-osp1 –  5.4.0.67.70
linux-image-oracle –  5.4.0.1039.36
linux-image-raspi –  5.4.0.1030.65
linux-image-raspi2 –  5.4.0.1030.65
linux-image-virtual –  5.4.0.67.70
18.04 bionic linux-image-5.4.0-1011-gkeop –  5.4.0-1011.12~18.04.2
linux-image-5.4.0-1030-raspi –  5.4.0-1030.33~18.04.1
linux-image-5.4.0-1037-gke –  5.4.0-1037.39~18.04.1
linux-image-5.4.0-1038-gcp –  5.4.0-1038.41~18.04.1
linux-image-5.4.0-1039-aws –  5.4.0-1039.41~18.04.1
linux-image-5.4.0-1039-oracle –  5.4.0-1039.42~18.04.1
linux-image-5.4.0-1041-azure –  5.4.0-1041.43~18.04.1
linux-image-5.4.0-67-generic –  5.4.0-67.75~18.04.1
linux-image-5.4.0-67-generic-lpae –  5.4.0-67.75~18.04.1
linux-image-5.4.0-67-lowlatency –  5.4.0-67.75~18.04.1
linux-image-aws –  5.4.0.1039.23
linux-image-aws-edge –  5.4.0.1039.23
linux-image-azure –  5.4.0.1041.21
linux-image-azure-edge –  5.4.0.1041.21
linux-image-gcp –  5.4.0.1038.25
linux-image-gcp-edge –  5.4.0.1038.25
linux-image-generic-hwe-18.04 –  5.4.0.67.75~18.04.62
linux-image-generic-lpae-hwe-18.04 –  5.4.0.67.75~18.04.62
linux-image-gke-5.4 –  5.4.0.1037.39~18.04.5
linux-image-gkeop-5.4 –  5.4.0.1011.12~18.04.12
linux-image-lowlatency-hwe-18.04 –  5.4.0.67.75~18.04.62
linux-image-oem –  5.4.0.67.75~18.04.62
linux-image-oem-osp1 –  5.4.0.67.75~18.04.62
linux-image-oracle –  5.4.0.1039.42~18.04.22
linux-image-raspi-hwe-18.04 –  5.4.0.1030.33
linux-image-snapdragon-hwe-18.04 –  5.4.0.67.75~18.04.62
linux-image-virtual-hwe-18.04 –  5.4.0.67.75~18.04.62

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References

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