SB2026100956 - NULL pointer dereference in Linux kernel ipv6 netfilter



SB2026100956 - NULL pointer dereference in Linux kernel ipv6 netfilter

Published: October 9, 2026

Security Bulletin ID SB2026100956
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) NULL pointer dereference (CVE-ID: CVE-2026-98379)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service by triggering a kernel panic.

The vulnerability exists due to a null pointer dereference in the Linux kernel IPv6 reverse-path filtering component when processing a route without an inet6_dev. A local user can use rtnetlink to lower an external nexthop device's MTU below IPV6_MIN_MTU and trigger an IPv6 reverse-path filtering lookup to cause a denial of service by triggering a kernel panic.

An unprivileged user can construct the required state within a private user namespace and network namespace.


Remediation

Install update from vendor's website.