---
id: CVE-2026-31407
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: conntrack: add missing netlink policy validations

  Hyunwoo Kim reports out-of-bounds access in sctp and ctnetlink.

  These attributes are used by the kernel w…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: conntrack: add missing netlink policy validations

  Hyunwoo Kim reports out-of-bounds access in sctp and ctnetlink.

  These attributes are used by the kernel w…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H'
cwe:
  - CWE-787
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.27, < 6.6.136'
  - 'linux_kernel >= 6.7, < 6.12.83'
  - 'linux_kernel >= 6.13, < 6.18.24'
  - 'linux_kernel >= 6.19, < 6.19.10'
  - linux_kernel = 7.0
patched:
  - linux_kernel 6.19.10
published: '2026-04-06'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:19:02.410'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-31407'
references:
  - url: 'https://git.kernel.org/stable/c/0fbae1e74493d5a160a70c51aeba035d8266ea7d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/67c53c1978cef3c504237275e39c857e2f6af56e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/78bba9f73942aa7dca47d817d8cec0fb9b443b70'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9174d28f3f15d8c4962f5980c0be167633880443'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/be88a337bf07afb1ee173f1099294d1b7ab3fefe'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c5e918390002edf0cff80a0e7ce1f86f16a9507c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e7b5766693477c52424cc6c79dd30a7a9c7db52c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f900e1d77ee0ef87bfb5ab3fe60f0b3d8ad5ba05'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00167
epssPercentile: 0.05516
ingestedAt: '2026-10-15T03:30:12.852Z'
---

## Overview

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

netfilter: conntrack: add missing netlink policy validations

Hyunwoo Kim reports out-of-bounds access in sctp and ctnetlink.

These attributes are used by the kernel without any validation.
Extend the netlink policies accordingly.

Quoting the reporter:
  nlattr_to_sctp() assigns the user-supplied CTA_PROTOINFO_SCTP_STATE
  value directly to ct->proto.sctp.state without checking that it is
  within the valid range. [..]

  and: ... with exp->dir = 100, the access at
  ct->master->tuplehash[100] reads 5600 bytes past the start of a
  320-byte nf_conn object, causing a slab-out-of-bounds read confirmed by
  UBSAN.

## Affected

- `linux_kernel >= 2.6.27, < 6.6.136`
- `linux_kernel >= 6.7, < 6.12.83`
- `linux_kernel >= 6.13, < 6.18.24`
- `linux_kernel >= 6.19, < 6.19.10`
- `linux_kernel = 7.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.19.10`