SB20261023118 - NULL pointer dereference in Linux kernel ipv6

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Main Vulnerability Database SB20261023118

SB20261023118 - NULL pointer dereference in Linux kernel ipv6

Published: October 23, 2026

Security Bulletin ID SB20261023118
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-2026-99041)

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 ip6erspan_tunnel_xmit() when obsolete path MTU handling treats tunnel metadata attached to a packet as a route with an output device. A local user can use tc tunnel_key to attach METADATA_IP_TUNNEL metadata and mirred to redirect the packet to a native ip6erspan device to trigger a kernel panic.

The reported reproduction used self-created user and network namespaces.


Remediation

Install update from vendor's website.

References