---
id: CVE-2026-46120
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ip6_gre: Use cached t->net in ip6erspan_changelink().

  After commit 5e72ce3e3980 ("net: ipv6: Use link netns in newlink() of
  rtnl_link_ops"), ip6erspan_newlink() correc…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ip6_gre: Use cached t->net in ip6erspan_changelink().

  After commit 5e72ce3e3980 ("net: ipv6: Use link netns in newlink() of
  rtnl_link_ops"), ip6erspan_newlink() correc…
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'
cwe:
  - CWE-416
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 4.16.12, < 4.17'
  - 'linux_kernel >= 4.17.1, < 5.10.258'
  - 'linux_kernel >= 5.11, < 5.15.209'
  - 'linux_kernel >= 5.16, < 6.1.175'
  - 'linux_kernel >= 6.2, < 6.6.140'
  - 'linux_kernel >= 6.7, < 6.12.88'
  - 'linux_kernel >= 6.13, < 6.18.30'
  - 'linux_kernel >= 6.19, < 7.0.7'
  - linux_kernel = 4.17
  - linux_kernel = 7.1
patched:
  - linux_kernel 7.0.7
published: '2026-05-28'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:19:44.523'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-46120'
references:
  - url: 'https://git.kernel.org/stable/c/01b71ff2857d3598337de11e7840a8e3ff21553c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/0fcf6731706f73494245a9c0d64f93bebf95bb51'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/1d324c2f43f70c965f25c58cc3611c779adbe47e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/311fdd26eb4443d43b909cc67a10f3a5fd1b21b2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7bd0f2b162b426b343a114e1b329f0d8d14fdc6e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cf7fc624329e76c6394653d12353e1d033adea91'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e70cfb40c3a99b232cd42c6a6a10f0d8e039dc82'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/eca62bb0569de4d43a4dac06a2092a9d4ca1d702'
    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: 0.00126
epssPercentile: 0.02027
ingestedAt: '2026-10-15T03:30:12.888Z'
---

## Overview

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

ip6_gre: Use cached t->net in ip6erspan_changelink().

After commit 5e72ce3e3980 ("net: ipv6: Use link netns in newlink() of
rtnl_link_ops"), ip6erspan_newlink() correctly resolves the per-netns
ip6gre hash via link_net. ip6erspan_changelink() was not converted in
that series and still uses dev_net(dev), which diverges from the
device's creation netns after IFLA_NET_NS_FD migration.

This re-inserts the tunnel into the wrong per-netns hash. The
original netns keeps a stale entry. When that netns is later
destroyed, ip6gre_exit_rtnl_net() walks the stale entry, producing a
slab-use-after-free reported by KASAN, followed by a kernel BUG at
net/core/dev.c (LIST_POISON1) in unregister_netdevice_many_notify().

Reachable from an unprivileged user namespace (unshare --user
--map-root-user --net).

ip6gre_changelink() earlier in the same file already uses the cached
t->net; only ip6erspan_changelink() has the wrong shape.

## Affected

- `linux_kernel >= 4.16.12, < 4.17`
- `linux_kernel >= 4.17.1, < 5.10.258`
- `linux_kernel >= 5.11, < 5.15.209`
- `linux_kernel >= 5.16, < 6.1.175`
- `linux_kernel >= 6.2, < 6.6.140`
- `linux_kernel >= 6.7, < 6.12.88`
- `linux_kernel >= 6.13, < 6.18.30`
- `linux_kernel >= 6.19, < 7.0.7`
- `linux_kernel = 4.17`
- `linux_kernel = 7.1`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.7`