---
id: CVE-2026-43339
title: 'ipv6: prevent possible UaF in addrconf_permanent_addr()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ipv6: prevent possible UaF in addrconf_permanent_addr()

  The mentioned helper try to warn the user about an exceptional
  condition, but the message is delivered too late…
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'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    eec49a33611f20336b357b3953df44f1a02049e8
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    bacc7f31085c9820922f00bc7d79756ffa13123a
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    7bfafa1b0cd582983ebec6bb20f0a435528fe567
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    25357b670afb5b517096da783abaa5cc4bf8359e
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    3cd4efb5df72843dfac892d0b3c7a4a8bd926b65
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1
  - >-
    Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac <
    fd63f185979b047fb22a0dfc6bd94d0cab6a6a70
  - Linux 4.6
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:16:32.652568Z'
published: '2026-05-08'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:20:39.340Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-43339'
references:
  - url: 'https://git.kernel.org/stable/c/eec49a33611f20336b357b3953df44f1a02049e8'
  - url: 'https://git.kernel.org/stable/c/bacc7f31085c9820922f00bc7d79756ffa13123a'
  - url: 'https://git.kernel.org/stable/c/7bfafa1b0cd582983ebec6bb20f0a435528fe567'
  - url: 'https://git.kernel.org/stable/c/7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e'
  - url: 'https://git.kernel.org/stable/c/25357b670afb5b517096da783abaa5cc4bf8359e'
  - url: 'https://git.kernel.org/stable/c/3cd4efb5df72843dfac892d0b3c7a4a8bd926b65'
  - url: 'https://git.kernel.org/stable/c/2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1'
  - url: 'https://git.kernel.org/stable/c/fd63f185979b047fb22a0dfc6bd94d0cab6a6a70'
tags:
  - cve.org
epss: 0.00121
epssPercentile: 0.01749
ingestedAt: '2026-10-16T17:24:46.692Z'
---

## Overview

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

ipv6: prevent possible UaF in addrconf_permanent_addr()

The mentioned helper try to warn the user about an exceptional
condition, but the message is delivered too late, accessing the ipv6
after its possible deletion.

Reorder the statement to avoid the possible UaF; while at it, place the
warning outside the idev->lock as it needs no protection.

## Affected

- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < eec49a33611f20336b357b3953df44f1a02049e8`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < bacc7f31085c9820922f00bc7d79756ffa13123a`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < 7bfafa1b0cd582983ebec6bb20f0a435528fe567`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < 7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < 25357b670afb5b517096da783abaa5cc4bf8359e`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < 3cd4efb5df72843dfac892d0b3c7a4a8bd926b65`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < 2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1`
- `Linux >= f1705ec197e705b79ea40fe7a2cc5acfa1d3bfac < fd63f185979b047fb22a0dfc6bd94d0cab6a6a70`
- `Linux 4.6`

## Remediation

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