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Ubuntu Security Notice USN-6652-1
February 23, 2024

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

- Ubuntu 23.10

Summary:

Several security issues were fixed in the Linux kernel.

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

Details:

Marek Marczykowski-Górecki discovered that the Xen event channel
infrastructure implementation in the Linux kernel contained a race
condition. An attacker in a guest VM could possibly use this to cause a
denial of service (paravirtualized device unavailability). (CVE-2023-34324)

Zheng Wang discovered a use-after-free in the Renesas Ethernet AVB driver
in the Linux kernel during device removal. A privileged attacker could use
this to cause a denial of service (system crash). (CVE-2023-35827)

Tom Dohrmann discovered that the Secure Encrypted Virtualization (SEV)
implementation for AMD processors in the Linux kernel contained a race
condition when accessing MMIO registers. A local attacker in a SEV guest VM
could possibly use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2023-46813)

It was discovered that the io_uring subsystem in the Linux kernel contained
a race condition, leading to a null pointer dereference vulnerability. A
local attacker could use this to cause a denial of service (system crash).
(CVE-2023-46862)

It was discovered that a race condition existed in the ATM (Asynchronous
Transfer Mode) 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-2023-51780)

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 netfilter subsystem in the Linux kernel did not
properly validate inner tunnel netlink attributes, leading to a null
pointer dereference vulnerability. A local attacker could use this to cause
a denial of service (system crash). (CVE-2023-5972)

It was discovered that the TLS subsystem in the Linux kernel did not
properly perform cryptographic operations in some situations, leading to a
null pointer dereference vulnerability. A local attacker could use this to
cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2023-6176)

Jann Horn discovered that a race condition existed in the Linux kernel when
handling io_uring over sockets, 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-2023-6531)

Xingyuan Mo discovered that the netfilter subsystem in the Linux kernel did
not properly handle dynset expressions passed from userspace, leading to a
null pointer dereference vulnerability. A local attacker could use this to
cause a denial of service (system crash). (CVE-2023-6622)

Zhenghan Wang discovered that the generic ID allocator implementation in
the Linux kernel did not properly check for null bitmap when releasing IDs.
A local attacker could use this to cause a denial of service (system
crash). (CVE-2023-6915)

Robert Morris discovered that the CIFS network file system implementation
in the Linux kernel did not properly validate certain server commands
fields, leading to an out-of-bounds read vulnerability. An attacker could
use this to cause a denial of service (system crash) or possibly expose
sensitive information. (CVE-2024-0565)

Jann Horn discovered that the io_uring subsystem in the Linux kernel did
not properly handle the release of certain buffer rings. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2024-0582)

It was discovered that the TIPC protocol implementation in the Linux kernel
did not properly handle locking during tipc_crypto_key_revoke() operations.
A local attacker could use this to cause a denial of service (kernel
deadlock). (CVE-2024-0641)

Jann Horn discovered that the TLS subsystem in the Linux kernel did not
properly handle spliced messages, leading to 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-2024-0646)

Update instructions:

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

Ubuntu 23.10:
   linux-image-6.5.0-1015-azure    6.5.0-1015.15
   linux-image-6.5.0-1015-azure-fde  6.5.0-1015.15
   linux-image-azure               6.5.0.1015.17
   linux-image-azure-fde           6.5.0.1015.17

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-6652-1
   CVE-2023-34324, CVE-2023-35827, CVE-2023-46813, CVE-2023-46862,
   CVE-2023-51780, CVE-2023-51781, CVE-2023-5972, CVE-2023-6176,
   CVE-2023-6531, CVE-2023-6622, CVE-2023-6915, CVE-2024-0565,
   CVE-2024-0582, CVE-2024-0641, CVE-2024-0646

Package Information:
   https://launchpad.net/ubuntu/+source/linux-azure/6.5.0-1015.15