---
id: CVE-2026-23293
title: 'net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled

  When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
  initialized because inet6_init() ex…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    649e2bb74da54c96cf20729001e283626a2fefa0
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    dc3e62cf3bbf66280a907ec379f373d0c3b8b2bc
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    b5190fcd75a1f1785c766a8d1e44d3938e168f45
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    5f93e6b4d12bd3a4517a6d447ea675f448f21434
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    f0373e9317bc904e7bdb123d3106fe4f3cea2fb7
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    fbbd2118982c55fb9b0a753ae0cf7194e77149fb
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    abcd48ecdeb2e12eccb8339a35534c757782afcd
  - >-
    Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 <
    168ff39e4758897d2eee4756977d036d52884c7e
  - Linux 3.12
published: '2026-03-25'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T08:45:25.692Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-23293'
references:
  - url: 'https://git.kernel.org/stable/c/649e2bb74da54c96cf20729001e283626a2fefa0'
  - url: 'https://git.kernel.org/stable/c/dc3e62cf3bbf66280a907ec379f373d0c3b8b2bc'
  - url: 'https://git.kernel.org/stable/c/b5190fcd75a1f1785c766a8d1e44d3938e168f45'
  - url: 'https://git.kernel.org/stable/c/5f93e6b4d12bd3a4517a6d447ea675f448f21434'
  - url: 'https://git.kernel.org/stable/c/f0373e9317bc904e7bdb123d3106fe4f3cea2fb7'
  - url: 'https://git.kernel.org/stable/c/fbbd2118982c55fb9b0a753ae0cf7194e77149fb'
  - url: 'https://git.kernel.org/stable/c/abcd48ecdeb2e12eccb8339a35534c757782afcd'
  - url: 'https://git.kernel.org/stable/c/168ff39e4758897d2eee4756977d036d52884c7e'
tags:
  - cve.org
epss: 0.00129
epssPercentile: 0.02879
ingestedAt: '2026-09-08T15:33:26.993Z'
---

## Overview

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

net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled

When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called
which initializes it. If an IPv6 packet is injected into the interface,
route_shortcircuit() is called and a NULL pointer dereference happens on
neigh_lookup().

 BUG: kernel NULL pointer dereference, address: 0000000000000380
 Oops: Oops: 0000 [#1] SMP NOPTI
 [...]
 RIP: 0010:neigh_lookup+0x20/0x270
 [...]
 Call Trace:
  <TASK>
  vxlan_xmit+0x638/0x1ef0 [vxlan]
  dev_hard_start_xmit+0x9e/0x2e0
  __dev_queue_xmit+0xbee/0x14e0
  packet_sendmsg+0x116f/0x1930
  __sys_sendto+0x1f5/0x200
  __x64_sys_sendto+0x24/0x30
  do_syscall_64+0x12f/0x1590
  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fix this by adding an early check on route_shortcircuit() when protocol
is ETH_P_IPV6. Note that ipv6_mod_enabled() cannot be used here because
VXLAN can be built-in even when IPv6 is built as a module.

## Affected

- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < 649e2bb74da54c96cf20729001e283626a2fefa0`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < dc3e62cf3bbf66280a907ec379f373d0c3b8b2bc`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < b5190fcd75a1f1785c766a8d1e44d3938e168f45`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < 5f93e6b4d12bd3a4517a6d447ea675f448f21434`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < f0373e9317bc904e7bdb123d3106fe4f3cea2fb7`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < fbbd2118982c55fb9b0a753ae0cf7194e77149fb`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < abcd48ecdeb2e12eccb8339a35534c757782afcd`
- `Linux >= e15a00aafa4b7953ad717d3cb1ad7acf4ff76945 < 168ff39e4758897d2eee4756977d036d52884c7e`
- `Linux 3.12`

## Remediation

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