USN-6344-1: Linux kernel (Azure) vulnerabilities

6 September 2023

Several security issues were fixed in the Linux kernel.

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Releases

Packages

  • linux-azure - Linux kernel for Microsoft Azure Cloud systems

Details

Zi Fan Tan discovered that the binder IPC implementation in the Linux
kernel contained 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-2023-21255)

It was discovered that a race condition existed in the f2fs file system in
the Linux kernel, leading to a null pointer dereference vulnerability. An
attacker could use this to construct a malicious f2fs image that, when
mounted and operated on, could cause a denial of service (system crash).
(CVE-2023-2898)

It was discovered that the DVB Core driver in the Linux kernel did not
properly handle locking events in certain situations. A local attacker
could use this to cause a denial of service (kernel deadlock).
(CVE-2023-31084)

Quentin Minster discovered that the KSMBD implementation in the Linux
kernel did not properly handle session setup requests. A remote attacker
could possibly use this to cause a denial of service (memory exhaustion).
(CVE-2023-32247)

Quentin Minster discovered that a race condition existed in the KSMBD
implementation in the Linux kernel when handling sessions operations. A
remote attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code. (CVE-2023-32250, CVE-2023-32252,
CVE-2023-32257)

It was discovered that a race condition existed in the KSMBD implementation
in the Linux kernel when handling session connections, leading to a use-
after-free vulnerability. A remote attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2023-32258)

It was discovered that the KSMBD implementation in the Linux kernel did not
properly validate buffer sizes in certain operations, 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-2023-38426, CVE-2023-38428)

It was discovered that the KSMBD implementation in the Linux kernel did not
properly calculate the size of certain buffers. A remote attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2023-38429)

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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 23.04

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.