---
id: CVE-2026-23391
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: xt_CT: drop pending enqueued packets on template removal

  Templates refer to objects that can go away while packets are sitting in
  nfqueue refer to:

  - helpe…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  netfilter: xt_CT: drop pending enqueued packets on template removal

  Templates refer to objects that can go away while packets are sitting in
  nfqueue refer to:

  - helpe…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 3.4.1, < 5.10.253'
  - 'linux_kernel >= 5.11, < 5.15.203'
  - 'linux_kernel >= 5.16, < 6.1.167'
  - 'linux_kernel >= 6.2, < 6.6.130'
  - 'linux_kernel >= 6.7, < 6.12.78'
  - 'linux_kernel >= 6.13, < 6.18.20'
  - 'linux_kernel >= 6.19, < 6.19.10'
  - linux_kernel = 3.4
  - linux_kernel = 7.0
patched:
  - linux_kernel 6.19.10
published: '2026-03-25'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:18:54.223'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23391'
references:
  - url: 'https://git.kernel.org/stable/c/19a230dec6bb8928e3f96387f9085cf2c79bcef9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/55445134d42b84cb0a272e42c98d233ca65eca83'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/63b8097cea1923fe82cd598068d0796da8c015ec'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/777d02efe3d630cca4c1b63962cec17c57711325'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cb549925875fa06dd155e49db4ac2c5044c30f9c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cc57506dd66555899560b9c0f24e813f034e12ec'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d2d0bae0c9a2a17b6990a2966f5cdce0813d6256'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f62a218a946b19bb59abdd5361da85fa4606b96b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-082556.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-457936.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00131
epssPercentile: 0.02689
ingestedAt: '2026-09-08T15:33:26.992Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:07:33.341687Z'
---

## Overview

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

netfilter: xt_CT: drop pending enqueued packets on template removal

Templates refer to objects that can go away while packets are sitting in
nfqueue refer to:

- helper, this can be an issue on module removal.
- timeout policy, nfnetlink_cttimeout might remove it.

The use of templates with zone and event cache filter are safe, since
this just copies values.

Flush these enqueued packets in case the template rule gets removed.

## Affected

- `linux_kernel >= 3.4.1, < 5.10.253`
- `linux_kernel >= 5.11, < 5.15.203`
- `linux_kernel >= 5.16, < 6.1.167`
- `linux_kernel >= 6.2, < 6.6.130`
- `linux_kernel >= 6.7, < 6.12.78`
- `linux_kernel >= 6.13, < 6.18.20`
- `linux_kernel >= 6.19, < 6.19.10`
- `linux_kernel = 3.4`
- `linux_kernel = 7.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.19.10`