USN-6412-1: Linux kernel vulnerabilities

5 October 2023

Several security issues were fixed in the Linux kernel.

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Releases

Packages

Details

Hyunwoo Kim discovered that the DVB Core driver in the Linux kernel
contained a race condition during device removal, leading to a use-after-
free vulnerability. A physically proximate attacker could use this to cause
a denial of service (system crash) or possibly execute arbitrary code.
(CVE-2022-45886, CVE-2022-45919)

Hyunwoo Kim discovered that the Technotrend/Hauppauge USB DEC driver in the
Linux kernel did not properly handle device removal events. A physically
proximate attacker could use this to cause a denial of service (system
crash). (CVE-2022-45887)

It was discovered that the NTFS file system implementation in the Linux
kernel did not properly validate MFT flags in certain situations. An
attacker could use this to construct a malicious NTFS image that, when
mounted and operated on, could cause a denial of service (system crash).
(CVE-2022-48425)

It was discovered that the IPv6 implementation in the Linux kernel
contained a high rate of hash collisions in connection lookup table. A
remote attacker could use this to cause a denial of service (excessive CPU
consumption). (CVE-2023-1206)

Daniel Trujillo, Johannes Wikner, and Kaveh Razavi discovered that some AMD
processors utilising speculative execution and branch prediction may allow
unauthorised memory reads via a speculative side-channel attack. A local
attacker could use this to expose sensitive information, including kernel
memory. (CVE-2023-20569)

It was discovered that the IPv6 RPL protocol implementation in the Linux
kernel did not properly handle user-supplied data. A remote attacker could
use this to cause a denial of service (system crash). (CVE-2023-2156)

Yang Lan discovered that the GFS2 file system implementation in the Linux
kernel could attempt to dereference a null pointer in some situations. An
attacker could use this to construct a malicious GFS2 image that, when
mounted and operated on, could cause a denial of service (system crash).
(CVE-2023-3212)

It was discovered that the KSMBD implementation in the Linux kernel did not
properly validate buffer sizes in certain operations, leading to an integer
underflow and out-of-bounds read vulnerability. A remote attacker could use
this to cause a denial of service (system crash) or possibly expose
sensitive information. (CVE-2023-38427)

Chih-Yen Chang discovered that the KSMBD implementation in the Linux kernel
did not properly validate packet header sizes in certain situations,
leading to an out-of-bounds read vulnerability. A remote attacker could use
this to cause a denial of service (system crash) or possibly expose
sensitive information. (CVE-2023-38431)

Andy Nguyen discovered that the KVM implementation for AMD processors in
the Linux kernel with Secure Encrypted Virtualization (SEV) contained a
race condition when accessing the GHCB page. A local attacker in a SEV
guest VM could possibly use this to cause a denial of service (host system
crash). (CVE-2023-4155)

It was discovered that the TUN/TAP driver in the Linux kernel did not
properly initialize socket data. A local attacker could use this to cause a
denial of service (system crash). (CVE-2023-4194)

Maxim Suhanov discovered that the exFAT file system implementation in the
Linux kernel did not properly check a file name length, leading to an out-
of-bounds write vulnerability. An attacker could use this to construct a
malicious exFAT image that, when mounted and operated on, could cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-4273)

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Update instructions

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

Ubuntu 23.04
Ubuntu 22.04

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.