==========================================================================
Ubuntu Security Notice USN-6494-2
November 30, 2023

linux-azure, linux-azure-4.15, linux-gcp, linux-gcp-4.15 vulnerabilities
==========================================================================

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

- Ubuntu 18.04 LTS (Available with Ubuntu Pro)
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)
- Ubuntu 14.04 LTS (Available with Ubuntu Pro)

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-azure-4.15: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp-4.15: Linux kernel for Google Cloud Platform (GCP) systems
- linux-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems

Details:

Yu Hao discovered that the UBI driver in the Linux kernel did not properly
check for MTD with zero erasesize during device attachment. A local
privileged attacker could use this to cause a denial of service (system
crash). (CVE-2023-31085)

Lucas Leong discovered that the netfilter subsystem in the Linux kernel did
not properly validate some attributes passed from userspace. A local
attacker could use this to cause a denial of service (system crash) or
possibly expose sensitive information (kernel memory). (CVE-2023-39189)

Sunjoo Park discovered that the netfilter subsystem in the Linux kernel did
not properly validate u32 packets content, leading to an out-of-bounds read
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly expose sensitive information. (CVE-2023-39192)

Lucas Leong discovered that the netfilter subsystem in the Linux kernel did
not properly validate SCTP data, leading to an out-of-bounds read
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly expose sensitive information. (CVE-2023-39193)

Lucas Leong discovered that the Netlink Transformation (XFRM) subsystem in
the Linux kernel did not properly handle state filters, leading to an out-
of-bounds read vulnerability. A privileged local attacker could use this to
cause a denial of service (system crash) or possibly expose sensitive
information. (CVE-2023-39194)

Kyle Zeng discovered that the IPv4 implementation in the Linux kernel did
not properly handle socket buffers (skb) when performing IP routing in
certain circumstances, leading to a null pointer dereference vulnerability.
A privileged attacker could use this to cause a denial of service (system
crash). (CVE-2023-42754)

It was discovered that the USB ENE card reader driver in the Linux kernel
did not properly allocate enough memory when processing the storage device
boot blocks. A local attacker could use this to cause a denial of service
(system crash). (CVE-2023-45862)

Manfred Rudigier discovered that the Intel(R) PCI-Express Gigabit (igb)
Ethernet driver in the Linux kernel did not properly validate received
frames that are larger than the set MTU size, leading to a buffer overflow
vulnerability. An attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2023-45871)

Budimir Markovic discovered that the perf subsystem in the Linux kernel did
not properly handle event groups, 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-2023-5717)

Update instructions:

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

Ubuntu 18.04 LTS (Available with Ubuntu Pro):
   linux-image-4.15.0-1157-gcp     4.15.0-1157.174
   linux-image-4.15.0-1172-azure   4.15.0-1172.187
   linux-image-azure-lts-18.04     4.15.0.1172.140
   linux-image-gcp-lts-18.04       4.15.0.1157.171

Ubuntu 16.04 LTS (Available with Ubuntu Pro):
   linux-image-4.15.0-1157-gcp     4.15.0-1157.174~16.04.1
   linux-image-4.15.0-1172-azure   4.15.0-1172.187~16.04.1
   linux-image-azure               4.15.0.1172.156
   linux-image-gcp                 4.15.0.1157.147
   linux-image-gke                 4.15.0.1157.147

Ubuntu 14.04 LTS (Available with Ubuntu Pro):
   linux-image-4.15.0-1172-azure   4.15.0-1172.187~14.04.1
   linux-image-azure               4.15.0.1172.138

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-6494-2
   https://ubuntu.com/security/notices/USN-6494-1
   CVE-2023-31085, CVE-2023-39189, CVE-2023-39192, CVE-2023-39193,
   CVE-2023-39194, CVE-2023-42754, CVE-2023-45862, CVE-2023-45871,
   CVE-2023-5717