USN-6700-1: Linux kernel vulnerabilities

18 March 2024

Several security issues were fixed in the Linux kernel.

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Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

It was discovered that the Layer 2 Tunneling Protocol (L2TP) implementation
in the Linux kernel contained a race condition when releasing PPPoL2TP
sockets in certain conditions, 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-2022-20567)

It was discovered that the ext4 file system implementation in the Linux
kernel did not properly handle block device modification while it is
mounted. A privileged attacker could use this to cause a denial of service
(system crash) or possibly expose sensitive information. (CVE-2023-34256)

Eric Dumazet discovered that the netfilter subsystem in the Linux kernel
did not properly handle DCCP conntrack buffers in certain situations,
leading to an out-of-bounds read vulnerability. An attacker could possibly
use this to expose sensitive information (kernel memory). (CVE-2023-39197)

It was discovered that a race condition existed in the AppleTalk networking
subsystem of the Linux kernel, 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-2023-51781)

It was discovered that the ext4 file system implementation in the Linux
kernel did not properly handle the remount operation in certain cases,
leading to a use-after-free vulnerability. A local attacker could use this
to cause a denial of service (system crash) or possibly expose sensitive
information. (CVE-2024-0775)

Notselwyn discovered that the netfilter subsystem in the Linux kernel did
not properly handle verdict parameters in certain cases, 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-2024-1086)

It was discovered that a race condition existed in the SCSI Emulex
LightPulse Fibre Channel driver in the Linux kernel when unregistering FCF
and re-scanning an HBA FCF table, leading to a null pointer dereference
vulnerability. A local attacker could use this to cause a denial of service
(system crash). (CVE-2024-24855)

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Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 16.04
Ubuntu 14.04

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.