---
id: CVE-2026-98573
title: >-
  kernel: net: skbuff: fix pull-bound underflow in skb_checksum_setup_ipv6()
  (CVE-2026-98573)
summary: >-
  A flaw was found in the Linux kernel. An integer underflow in the networking
  subsystem allows an attacker to trigger an out-of-bounds memory copy by
  sending specially crafted Internet Protocol version 6 (IPv6) packets with
  extension header…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-191
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 7
  - enterprise_linux 8
  - enterprise_linux 9
  - openshift_container_platform 4
  - enterprise_linux 6
published: '2026-10-18'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T03:22:33+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98573.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98573.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98573'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2554955'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98573'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98573'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98573.mbox
  - url: 'https://git.kernel.org/stable/c/9c4e432132a97b82edf28fa172c39f743e6bfb26'
  - url: 'https://git.kernel.org/stable/c/718747afa5463d9cc5fd9a09f03b2a492edd9b78'
  - url: 'https://git.kernel.org/stable/c/a0ad0473c09d2e947aecac5c82e637ec85924b12'
  - url: 'https://git.kernel.org/stable/c/b2da5ed3d8c75e1b729a21b6d3beaed415e263f6'
  - url: 'https://git.kernel.org/stable/c/6c28c31f051dbf49c71ba7ab7bb9bc905fa1d14b'
  - url: 'https://git.kernel.org/stable/c/cfa643f2ca36c6f913fe1a2ceb12412ebb0fd962'
  - url: 'https://git.kernel.org/stable/c/d7f474226809471dc7877435e9c492cc914df0bf'
  - url: 'https://git.kernel.org/stable/c/3b4e0b0c008a8c1b474730248cd5b873026c74bd'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00216
epssPercentile: 0.11992
ingestedAt: '2026-10-18T15:45:12.257Z'
---

## Overview

A flaw was found in the Linux kernel. An integer underflow in the networking subsystem allows an attacker to trigger an out-of-bounds memory copy by sending specially crafted Internet Protocol version 6 (IPv6) packets with extension headers. This vulnerability can lead to kernel memory corruption, resulting in a system crash and a Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4, Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98573.json)

**kernel: net: skbuff: fix pull-bound underflow in skb_checksum_setup_ipv6()** — rated Important by Red Hat. Released 2026-10-18, updated 2026-10-20.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4
- Red Hat Enterprise Linux 6

No fix planned:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Affected