---
id: CVE-2026-72253
title: 'netfilter: nf_conntrack_sip: validate skb_dst() before accessing it'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: nf_conntrack_sip: validate skb_dst() before accessing it

  tc ingress and openvswitch do not guarantee routing information to be
  available. These subsystems u…
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: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    7866116a040b3a23fb094e7d8f7ea3d61b3ac70b
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    c5ef7228be04518d95591fc5369a9c554b19756d
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    0aec339694a56e263d4b22475ff7211d40900830
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    e64a48c50a1ff565a98c6a98d82b5b942868e76e
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    c199ed687c00841daf60e9d131976958583a8c09
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    09755dc62b026076b1d47f83489eb0547c8135e0
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    b843a96252f672332837ea2ecb7c8db0acf68e20
  - >-
    Linux >= cae3a2627520c3795b54533c5328b77af3405dbe <
    e5e24a365a5e024efef63cc49abb345fbd4852c5
  - Linux 4.3
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-16T18:45:17.838636Z'
published: '2026-08-15'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T18:55:13.536Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-72253'
references:
  - url: 'https://git.kernel.org/stable/c/7866116a040b3a23fb094e7d8f7ea3d61b3ac70b'
  - url: 'https://git.kernel.org/stable/c/c5ef7228be04518d95591fc5369a9c554b19756d'
  - url: 'https://git.kernel.org/stable/c/0aec339694a56e263d4b22475ff7211d40900830'
  - url: 'https://git.kernel.org/stable/c/e64a48c50a1ff565a98c6a98d82b5b942868e76e'
  - url: 'https://git.kernel.org/stable/c/c199ed687c00841daf60e9d131976958583a8c09'
  - url: 'https://git.kernel.org/stable/c/09755dc62b026076b1d47f83489eb0547c8135e0'
  - url: 'https://git.kernel.org/stable/c/b843a96252f672332837ea2ecb7c8db0acf68e20'
  - url: 'https://git.kernel.org/stable/c/e5e24a365a5e024efef63cc49abb345fbd4852c5'
tags:
  - cve.org
epss: 0.00696
epssPercentile: 0.5205
ingestedAt: '2026-10-16T19:46:24.416Z'
---

## Overview

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

netfilter: nf_conntrack_sip: validate skb_dst() before accessing it

tc ingress and openvswitch do not guarantee routing information to be
available. These subsystems use the conntrack helper infrastructure, and
the SIP helper relies on the skb_dst() to be present if
sip_external_media is set to 1 (which is disabled by default as a module
parameter).

This effectively disables the sip_external_media toggle for these
subsystems without resulting in a crash.

## Affected

- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < 7866116a040b3a23fb094e7d8f7ea3d61b3ac70b`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < c5ef7228be04518d95591fc5369a9c554b19756d`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < 0aec339694a56e263d4b22475ff7211d40900830`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < e64a48c50a1ff565a98c6a98d82b5b942868e76e`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < c199ed687c00841daf60e9d131976958583a8c09`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < 09755dc62b026076b1d47f83489eb0547c8135e0`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < b843a96252f672332837ea2ecb7c8db0acf68e20`
- `Linux >= cae3a2627520c3795b54533c5328b77af3405dbe < e5e24a365a5e024efef63cc49abb345fbd4852c5`
- `Linux 4.3`

## Remediation

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