---
id: CVE-2026-68142
title: 'geneve: require CAP_NET_ADMIN in the device netns for changelink'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  geneve: require CAP_NET_ADMIN in the device netns for changelink

  A tunnel changelink() operates on at most two netns, dev_net(dev) and
  the sticky underlay netns geneve…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    a5522963c57f12df5f9db804ebfc472b58eef0ae
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    278c6a31ee27c931c722202c8c06cc3253923254
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    11a7d989d00160481a273eb4f7f05f64b5a6ffdf
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    2abdacc927c92fa6a9cc8341e8c9b88dcb561553
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    9de5518fc1fab583526a8f66b8e505c4864dc60a
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    f8c498585d2a08aa623748353c3e61467b7e9fd2
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    95f45e20f1b2cec13823f0f68060ab4b2261b2c1
  - >-
    Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a <
    8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01
  - Linux 4.14
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:44:41.067135Z'
published: '2026-08-10'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:52:59.619Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-68142'
references:
  - url: 'https://git.kernel.org/stable/c/a5522963c57f12df5f9db804ebfc472b58eef0ae'
  - url: 'https://git.kernel.org/stable/c/278c6a31ee27c931c722202c8c06cc3253923254'
  - url: 'https://git.kernel.org/stable/c/11a7d989d00160481a273eb4f7f05f64b5a6ffdf'
  - url: 'https://git.kernel.org/stable/c/2abdacc927c92fa6a9cc8341e8c9b88dcb561553'
  - url: 'https://git.kernel.org/stable/c/9de5518fc1fab583526a8f66b8e505c4864dc60a'
  - url: 'https://git.kernel.org/stable/c/f8c498585d2a08aa623748353c3e61467b7e9fd2'
  - url: 'https://git.kernel.org/stable/c/95f45e20f1b2cec13823f0f68060ab4b2261b2c1'
  - url: 'https://git.kernel.org/stable/c/8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01'
tags:
  - cve.org
epss: 0.00139
epssPercentile: 0.02893
ingestedAt: '2026-10-16T17:24:46.843Z'
---

## Overview

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

geneve: require CAP_NET_ADMIN in the device netns for changelink

A tunnel changelink() operates on at most two netns, dev_net(dev) and
the sticky underlay netns geneve->net. They differ once the device is
created in or moved to a netns other than the one the request runs in.
The rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev),
so a caller privileged there but not in geneve->net can rewrite a geneve
device whose underlay lives in geneve->net.

geneve_changelink() applies the new configuration against geneve->net:
geneve_link_config() and the geneve_quiesce()/geneve_unquiesce() pair
reopen the underlay sockets in that netns (geneve_sock_add() uses
geneve->net), so the same reasoning as the tunnel changelink series
applies here.

Gate geneve_changelink() with rtnl_dev_link_net_capable(), at the top of
the op before any attribute is parsed, matching ipgre_changelink() and
the rest of the "require CAP_NET_ADMIN in the device netns for
changelink" series.

Found by 0sec automated security-research tooling (https://0sec.ai).

## Affected

- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < a5522963c57f12df5f9db804ebfc472b58eef0ae`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < 278c6a31ee27c931c722202c8c06cc3253923254`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < 11a7d989d00160481a273eb4f7f05f64b5a6ffdf`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < 2abdacc927c92fa6a9cc8341e8c9b88dcb561553`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < 9de5518fc1fab583526a8f66b8e505c4864dc60a`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < f8c498585d2a08aa623748353c3e61467b7e9fd2`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < 95f45e20f1b2cec13823f0f68060ab4b2261b2c1`
- `Linux >= 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a < 8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01`
- `Linux 4.14`

## Remediation

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