1. Ubuntu Security Notices
  2. USN-5113-1

USN-5113-1: Linux kernel vulnerabilities

Publication date

19 October 2021

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

Details

It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)

Alois Wohlschlager discovered that the overlay file system in the Linux
kernel did not restrict private clones in some situations. An attacker
could use this to expose sensitive information. (CVE-2021-3732)

It was discovered that the btrfs file system in the Linux kernel did not
properly handle removing a non-existent device id. An attacker with
CAP_SYS_ADMIN could use this to cause a denial of service. (CVE-2021-3739)

It was discovered that the Qualcomm IPC Router protocol implementation in
the Linux kernel did not properly validate metadata in some situations. A
local attacker could use this to cause a...

It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)

Alois Wohlschlager discovered that the overlay file system in the Linux
kernel did not restrict private clones in some situations. An attacker
could use this to expose sensitive information. (CVE-2021-3732)

It was discovered that the btrfs file system in the Linux kernel did not
properly handle removing a non-existent device id. An attacker with
CAP_SYS_ADMIN could use this to cause a denial of service. (CVE-2021-3739)

It was discovered that the Qualcomm IPC Router protocol implementation in
the Linux kernel did not properly validate metadata in some situations. A
local attacker could use this to cause a denial of service (system crash)
or expose sensitive information. (CVE-2021-3743)

It was discovered that the virtual terminal (vt) device implementation in
the Linux kernel contained a race condition in its ioctl handling that led
to an out-of-bounds read vulnerability. A local attacker could possibly use
this to expose sensitive information. (CVE-2021-3753)

It was discovered that the BPF subsystem in the Linux kernel contained an
integer overflow in its hash table implementation. A local attacker could
use this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2021-38166)

It was discovered that the ext4 file system in the Linux kernel contained a
race condition when writing xattrs to an inode. A local attacker could use
this to cause a denial of service or possibly gain administrative
privileges. (CVE-2021-40490)

It was discovered that the 6pack network protocol driver in the Linux
kernel did not properly perform validation checks. A privileged attacker
could use this to cause a denial of service (system crash) or execute
arbitrary code. (CVE-2021-42008)

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
21.04 hirsute linux-image-5.11.0-1021-raspi-nolpae –  5.11.0-1021.22
linux-image-virtual –  5.11.0.38.39
linux-image-generic-64k –  5.11.0.38.39
linux-image-generic –  5.11.0.38.39
linux-image-5.11.0-38-lowlatency –  5.11.0-38.42
linux-image-5.11.0-38-generic-lpae –  5.11.0-38.42
linux-image-aws –  5.11.0.1020.21
linux-image-oracle –  5.11.0.1020.21
linux-image-5.11.0-1020-azure –  5.11.0-1020.21
linux-image-5.11.0-38-generic –  5.11.0-38.42
linux-image-5.11.0-1018-kvm –  5.11.0-1018.19
linux-image-azure –  5.11.0.1020.21
linux-image-raspi-nolpae –  5.11.0.1021.19
linux-image-oem-20.04 –  5.11.0.38.39
linux-image-gke –  5.11.0.1021.21
linux-image-gcp –  5.11.0.1021.21
linux-image-5.11.0-1021-gcp –  5.11.0-1021.23
linux-image-5.11.0-1020-aws –  5.11.0-1020.21
linux-image-raspi –  5.11.0.1021.19
linux-image-5.11.0-1020-oracle –  5.11.0-1020.21
linux-image-kvm –  5.11.0.1018.19
linux-image-generic-lpae –  5.11.0.38.39
linux-image-lowlatency –  5.11.0.38.39
linux-image-5.11.0-38-generic-64k –  5.11.0-38.42
linux-image-5.11.0-1021-raspi –  5.11.0-1021.22
20.04 focal linux-image-virtual-hwe-20.04 –  5.11.0.38.42~20.04.17
linux-image-azure-edge –  5.11.0.1020.21~20.04.19
linux-image-5.11.0-38-lowlatency –  5.11.0-38.42~20.04.1
linux-image-5.11.0-38-generic-lpae –  5.11.0-38.42~20.04.1
linux-image-aws –  5.11.0.1020.21~20.04.19
linux-image-oracle –  5.11.0.1020.21~20.04.13
linux-image-5.11.0-1020-azure –  5.11.0-1020.21~20.04.1
linux-image-lowlatency-hwe-20.04 –  5.11.0.38.42~20.04.17
linux-image-generic-hwe-20.04 –  5.11.0.38.42~20.04.17
linux-image-gcp –  5.11.0.1021.23~20.04.20
linux-image-5.11.0-1021-gcp –  5.11.0-1021.23~20.04.1
linux-image-5.11.0-1020-aws –  5.11.0-1020.21~20.04.2
linux-image-generic-lpae-hwe-20.04 –  5.11.0.38.42~20.04.17
linux-image-5.11.0-38-generic –  5.11.0-38.42~20.04.1
linux-image-generic-64k-hwe-20.04 –  5.11.0.38.42~20.04.17
linux-image-5.11.0-1020-oracle –  5.11.0-1020.21~20.04.1
linux-image-5.11.0-38-generic-64k –  5.11.0-38.42~20.04.1

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References

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