SB2023103102 - Ubuntu update for linux



SB2023103102 - Ubuntu update for linux

Published: October 31, 2023 Updated: January 4, 2026

Security Bulletin ID SB2023103102
Severity
Medium
Patch available
YES
Number of vulnerabilities 7
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Medium 14% Low 86%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 7 secuirty vulnerabilities.


1) Resource exhaustion (CVE-ID: CVE-2023-1206)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a hash collision flaw in the IPv6 connection lookup table in the Linux kernel’s IPv6 functionality when an attacker makes a new kind of SYN flood attack. A remote attacker can increase the CPU usage of the server that accepts IPV6 connections up to 95%.


2) Out-of-bounds read (CVE-ID: CVE-2023-1380)

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition within the Broadcom Full MAC Wi-Fi driver (brcmfmac.ko). A local user can trigger an out-of-bounds read error and read contents of kernel memory on the system.


3) Out-of-bounds write (CVE-ID: CVE-2023-31436)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error within the qfq_change_class() function in net/sched/sch_qfq.c when handling the MTU value provided to the QFQ Scheduler. A local user can trigger an out-of-bounds write and execute arbitrary code with elevated privileges.


4) Out-of-bounds write (CVE-ID: CVE-2023-35001)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error within the nft_byteorder() function. A local user can trigger an out-of-bounds write and execute arbitrary code on the target system.


5) Integer overflow (CVE-ID: CVE-2023-42752)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to integer overflow within the __alloc_skb() function. A local user can trigger integer overflow and crash the kernel.


6) Out-of-bounds read (CVE-ID: CVE-2023-42755)

The vulnerability allows a local user to perform denial of service (DoS) attack.

The vulnerability exists due to a boundary condition within the the IPv4 Resource Reservation Protocol (RSVP) classifier function in the Linux kernel. A local user can trigger an out-of-bounds read error and crash the Linux kernel.


7) Use-after-free (CVE-ID: CVE-2023-4623)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the the Linux kernel net/sched: sch_hfsc (HFSC qdisc traffic control) component. A local user can trigger a use-after-free error and execute arbitrary code with elevated privileges.


Remediation

Install update from vendor's website.