USN-6315-1: Linux kernel vulnerabilities

29 August 2023

Several security issues were fixed in the Linux kernel.

Reduce your security exposure

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

Releases

Packages

Details

Daniel Moghimi discovered that some Intel(R) Processors did not properly
clear microarchitectural state after speculative execution of various
instructions. A local unprivileged user could use this to obtain to
sensitive information. (CVE-2022-40982)

Tavis Ormandy discovered that some AMD processors did not properly handle
speculative execution of certain vector register instructions. A local
attacker could use this to expose sensitive information. (CVE-2023-20593)

Ye Zhang and Nicolas Wu discovered that the io_uring subsystem in the Linux
kernel did not properly handle locking for rings with IOPOLL, leading to a
double-free vulnerability. A local attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-21400)

It was discovered that the universal 32bit network packet classifier
implementation in the Linux kernel did not properly perform reference
counting in some situations, 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-2023-3609)

It was discovered that the netfilter subsystem in the Linux kernel did not
properly handle certain error 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-2023-3610)

It was discovered that the Quick Fair Queueing network scheduler
implementation in the Linux kernel contained an out-of-bounds write
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2023-3611)

It was discovered that the network packet classifier with
netfilter/firewall marks implementation in the Linux kernel did not
properly handle reference counting, 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-2023-3776)

Kevin Rich discovered that the netfilter subsystem in the Linux kernel did
not properly handle table rules flush in certain circumstances. A local
attacker could possibly use this to cause a denial of service (system
crash) or execute arbitrary code. (CVE-2023-3777)

Kevin Rich discovered that the netfilter subsystem in the Linux kernel did
not properly handle rule additions to bound chains in certain
circumstances. A local attacker could possibly use this to cause a denial
of service (system crash) or execute arbitrary code. (CVE-2023-3995)

It was discovered that the netfilter subsystem in the Linux kernel did not
properly handle PIPAPO element removal, leading to a use-after-free
vulnerability. A local attacker could possibly use this to cause a denial
of service (system crash) or execute arbitrary code. (CVE-2023-4004)

Kevin Rich discovered that the netfilter subsystem in the Linux kernel did
not properly handle bound chain deactivation in certain circumstances. A
local attacker could possibly use this to cause a denial of service (system
crash) or execute arbitrary code. (CVE-2023-4015)

Reduce your security exposure

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 22.04
Ubuntu 20.04

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.

References

Related notices

Join the discussion

Need help with your security needs?

Ubuntu Pro provides up to ten-year security coverage for over 23,000 open-source packages within the Ubuntu Main and Universe repositories.

Talk to an expert to find out what would work best for you

Further reading