==========================================================================
Ubuntu Security Notice USN-6726-2
April 16, 2024

linux-iot vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-iot: Linux kernel for IoT platforms

Details:

Pratyush Yadav discovered that the Xen network backend implementation in
the Linux kernel did not properly handle zero length data request, leading
to a null pointer dereference vulnerability. An attacker in a guest VM
could possibly use this to cause a denial of service (host domain crash).
(CVE-2023-46838)

It was discovered that the IPv6 implementation of the Linux kernel did not
properly manage route cache memory usage. A remote attacker could use this
to cause a denial of service (memory exhaustion). (CVE-2023-52340)

It was discovered that the device mapper driver in the Linux kernel did not
properly validate target size during certain memory allocations. A local
attacker could use this to cause a denial of service (system crash).
(CVE-2023-52429, CVE-2024-23851)

Dan Carpenter discovered that the netfilter subsystem in the Linux kernel
did not store data in properly sized memory locations. A local user could
use this to cause a denial of service (system crash). (CVE-2024-0607)

Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
   - Architecture specifics;
   - Cryptographic API;
   - Android drivers;
   - EDAC drivers;
   - GPU drivers;
   - Media drivers;
   - MTD block device drivers;
   - Network drivers;
   - NVME drivers;
   - TTY drivers;
   - Userspace I/O drivers;
   - F2FS file system;
   - GFS2 file system;
   - IPv6 Networking;
   - AppArmor security module;
(CVE-2023-52464, CVE-2023-52448, CVE-2023-52457, CVE-2023-52443,
CVE-2023-52439, CVE-2023-52612, CVE-2024-26633, CVE-2024-26597,
CVE-2023-52449, CVE-2023-52444, CVE-2023-52609, CVE-2023-52469,
CVE-2023-52445, CVE-2023-52451, CVE-2023-52470, CVE-2023-52454,
CVE-2023-52436, CVE-2023-52438)

Update instructions:

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

Ubuntu 20.04 LTS:
   linux-image-5.4.0-1034-iot      5.4.0-1034.35

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-6726-2
   https://ubuntu.com/security/notices/USN-6726-1
   CVE-2023-46838, CVE-2023-52340, CVE-2023-52429, CVE-2023-52436,
   CVE-2023-52438, CVE-2023-52439, CVE-2023-52443, CVE-2023-52444,
   CVE-2023-52445, CVE-2023-52448, CVE-2023-52449, CVE-2023-52451,
   CVE-2023-52454, CVE-2023-52457, CVE-2023-52464, CVE-2023-52469,
   CVE-2023-52470, CVE-2023-52609, CVE-2023-52612, CVE-2024-0607,
   CVE-2024-23851, CVE-2024-26597, CVE-2024-26633

Package Information:
   https://launchpad.net/ubuntu/+source/linux-iot/5.4.0-1034.35