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Ubuntu Security Notice USN-5541-1
July 28, 2022

linux-azure vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-azure: Linux kernel for Microsoft Azure Cloud systems

Details:

Eric Biederman discovered that the cgroup process migration implementation
in the Linux kernel did not perform permission checks correctly in some
situations. A local attacker could possibly use this to gain administrative
privileges. (CVE-2021-4197)

Jann Horn discovered that the FUSE file system 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-2022-1011)

Duoming Zhou discovered that the 6pack protocol implementation in the Linux
kernel did not handle detach events properly in some situations, leading to
a use-after-free vulnerability. A local attacker could use this to cause a
denial of service (system crash). (CVE-2022-1198)

Duoming Zhou discovered that the AX.25 amateur radio protocol
implementation in the Linux kernel did not handle detach events properly in
some situations. A local attacker could possibly use this to cause a denial
of service (system crash) or execute arbitrary code. (CVE-2022-1199)

Duoming Zhou discovered race conditions in the AX.25 amateur radio protocol
implementation in the Linux kernel during device detach operations. A local
attacker could possibly use this to cause a denial of service (system
crash). (CVE-2022-1204)

Duoming Zhou discovered race conditions in the AX.25 amateur radio protocol
implementation in the Linux kernel, leading to use-after-free
vulnerabilities. A local attacker could possibly use this to cause a denial
of service (system crash). (CVE-2022-1205)

It was discovered that the PF_KEYv2 implementation in the Linux kernel did
not properly initialize kernel memory in some situations. A local attacker
could use this to expose sensitive information (kernel memory).
(CVE-2022-1353)

It was discovered that the implementation of X.25 network protocols in the
Linux kernel did not terminate link layer sessions properly. A local
attacker could possibly use this to cause a denial of service (system
crash). (CVE-2022-1516)

Zheyu Ma discovered that the Silicon Motion SM712 framebuffer driver in the
Linux kernel did not properly handle very small reads. A local attacker
could use this to cause a denial of service (system crash). (CVE-2022-2380)

It was discovered that the 8 Devices USB2CAN interface implementation in
the Linux kernel did not properly handle certain error conditions, leading
to a double-free. A local attacker could possibly use this to cause a
denial of service (system crash). (CVE-2022-28388)

It was discovered that the Microchip CAN BUS Analyzer interface
implementation in the Linux kernel did not properly handle certain error
conditions, leading to a double-free. A local attacker could possibly use
this to cause a denial of service (system crash). (CVE-2022-28389)

Update instructions:

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

Ubuntu 16.04 ESM:
  linux-image-4.15.0-1146-azure   4.15.0-1146.161~16.04.1
  linux-image-azure               4.15.0.1146.133

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:
  https://ubuntu.com/security/notices/USN-5541-1
  CVE-2021-4197, CVE-2022-1011, CVE-2022-1198, CVE-2022-1199,
  CVE-2022-1204, CVE-2022-1205, CVE-2022-1353, CVE-2022-1516,
  CVE-2022-2380, CVE-2022-28388, CVE-2022-28389