SB20260816127 - Incorrect calculation in Linux kernel ipv6 netfilter



SB20260816127 - Incorrect calculation in Linux kernel ipv6 netfilter

Published: August 16, 2026

Security Bulletin ID SB20260816127
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) Incorrect calculation (CVE-ID: CVE-2026-72250)

CWE-ID: CWE-682 - Incorrect Calculation

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.

The vulnerability exists due to improper handling of an unset header offset in nf_ct_frag6_reasm() when processing IPv6 fragments on the NF_INET_LOCAL_OUT defragmentation path. A local user can send a specially crafted fragmented IPv6 packet to cause a denial of service.

The issue occurs because skb->mac_header may still hold the unset sentinel value when no link-layer header is present yet.


Remediation

Install update from vendor's website.