---
id: CVE-2026-80637
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: synproxy: fix unaligned memory access in timestamp adjustment

  Use get_unaligned_be32() and put_unaligned_be32() to safely read and
  write the timestamp field…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: synproxy: fix unaligned memory access in timestamp adjustment

  Use get_unaligned_be32() and put_unaligned_be32() to safely read and
  write the timestamp field…
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'
published: '2026-08-28'
updated: '2026-08-29'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80637'
references:
  - url: 'https://git.kernel.org/stable/c/2b8e7aaa38002d8ee2f48d87b1f392eadd8e98c4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5c9c67cf7a3d16051dfb90e98836f530964dfb8e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/992c20bc8a4aba220c8b95b467d049289778dad6'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ea3d2caa5bfacf5db5c1cad521ca5d9144edd9a7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80637.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-80637'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2525460'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-80637'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80637'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026082840-CVE-2026-80637-4cf0@gregkh/T
  - url: 'https://git.kernel.org/stable/c/95cda0446f51077c343fdd8264be2737eb25a6c3'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.0063
epssPercentile: 0.49967
ingestedAt: '2026-08-30T03:46:31.135Z'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 48b1de4c110a7afa4b85862f6c75af817db26fad <
    2b8e7aaa38002d8ee2f48d87b1f392eadd8e98c4
  - >-
    Linux >= 48b1de4c110a7afa4b85862f6c75af817db26fad <
    5c9c67cf7a3d16051dfb90e98836f530964dfb8e
  - >-
    Linux >= 48b1de4c110a7afa4b85862f6c75af817db26fad <
    ea3d2caa5bfacf5db5c1cad521ca5d9144edd9a7
  - >-
    Linux >= 48b1de4c110a7afa4b85862f6c75af817db26fad <
    992c20bc8a4aba220c8b95b467d049289778dad6
  - Linux 3.12
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-16T19:19:14.142885Z'
cwe:
  - CWE-468
scores:
  nvd: 7.5
  vendor: 5.5
  cna: 7.5
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

netfilter: synproxy: fix unaligned memory access in timestamp adjustment

Use get_unaligned_be32() and put_unaligned_be32() to safely read and
write the timestamp fields. This prevents performance degradation due to
unaligned memory access or even a crash on strict alignment
architectures.

This follows the implementation of timestamp parsing in the networking
stack at tcp_parse_options() and synproxy_parse_options().

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80637.json)