---
id: CVE-2022-32296
title: >-
  The Linux kernel before 5.17.9 allows TCP servers to identify clients by
  observing what source ports are used
summary: >-
  The Linux kernel before 5.17.9 allows TCP servers to identify clients by
  observing what source ports are used. This occurs because of use of Algorithm
  4 ("Double-Hash Port Selection Algorithm") of RFC 6056.
severity: low
cvss: 3.3
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-330
vendor: linux
product: linux_kernel
affected:
  - linux_kernel < 5.17.9
patched:
  - linux_kernel 5.17.9
published: '2022-06-05'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T17:17:40.420'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2022-32296'
references:
  - url: 'https://arxiv.org/abs/2209.12993'
    label: cve@mitre.org
  - url: 'https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.9'
    label: cve@mitre.org
  - url: >-
      https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4c2c8f03a5ab7cb04ec64724d7d176d00bcc91e5
    label: cve@mitre.org
  - url: 'https://github.com/0xkol/rfc6056-device-tracker'
    label: cve@mitre.org
  - url: 'https://lists.debian.org/debian-lts-announce/2022/07/msg00000.html'
    label: cve@mitre.org
  - url: 'https://www.debian.org/security/2022/dsa-5173'
    label: cve@mitre.org
  - url: 'https://arxiv.org/abs/2209.12993'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.9'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4c2c8f03a5ab7cb04ec64724d7d176d00bcc91e5
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/0xkol/rfc6056-device-tracker'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2022/07/msg00000.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.debian.org/security/2022/dsa-5173'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-419740.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-794697.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00438
epssPercentile: 0.36482
ingestedAt: '2026-10-14T17:44:53.598Z'
---

## Overview

The Linux kernel before 5.17.9 allows TCP servers to identify clients by observing what source ports are used. This occurs because of use of Algorithm 4 ("Double-Hash Port Selection Algorithm") of RFC 6056.

## Affected

- `linux_kernel < 5.17.9`

## Remediation

Upgrade past the affected range:

- `linux_kernel 5.17.9`