---
id: CVE-2026-23460
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net/rose: fix NULL pointer dereference in rose_transmit_link on reconnect

  syzkaller reported a bug [1], and the reproducer is available at [2].

  ROSE sockets use four …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net/rose: fix NULL pointer dereference in rose_transmit_link on reconnect

  syzkaller reported a bug [1], and the reproducer is available at [2].

  ROSE sockets use four …
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.12.1, < 5.10.253'
  - 'linux_kernel >= 5.11, < 5.15.203'
  - 'linux_kernel >= 5.16, < 6.1.167'
  - 'linux_kernel >= 6.2, < 6.6.130'
  - 'linux_kernel >= 6.7, < 6.12.78'
  - 'linux_kernel >= 6.13, < 6.18.20'
  - 'linux_kernel >= 6.19, < 6.19.10'
  - linux_kernel = 2.6.12
  - linux_kernel = 7.0
patched:
  - linux_kernel 6.19.10
published: '2026-04-03'
updated: '2026-07-24'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23460'
references:
  - url: 'https://git.kernel.org/stable/c/0c3e8bff808f17ad37a51d8e719eed22c7863120'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/0c9fb70a206a8734e10468ecc24d57c7596cf64e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/508f49ccbe0329641bb681f7d0052bb4e5943252'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a12254050e3050f1011cd24f3b880a6882d0139d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a753844d2a8136f090123c8fb1ff6c7f6ee7c2b3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c2ab74c12932e52cfa1e7e4582d42b0c8bec96c7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c85fe6580e86947ca07907ebf4363a73c156fda7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e1f0a18c9564cdb16523c802e2c6fe5874e3d944'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00123
epssPercentile: 0.01779
ingestedAt: '2026-07-25T22:05:03.518Z'
---

## Overview

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

net/rose: fix NULL pointer dereference in rose_transmit_link on reconnect

syzkaller reported a bug [1], and the reproducer is available at [2].

ROSE sockets use four sk->sk_state values: TCP_CLOSE, TCP_LISTEN,
TCP_SYN_SENT, and TCP_ESTABLISHED. rose_connect() already rejects
calls for TCP_ESTABLISHED (-EISCONN) and TCP_CLOSE with SS_CONNECTING
(-ECONNREFUSED), but lacks a check for TCP_SYN_SENT.

When rose_connect() is called a second time while the first connection
attempt is still in progress (TCP_SYN_SENT), it overwrites
rose->neighbour via rose_get_neigh(). If that returns NULL, the socket
is left with rose->state == ROSE_STATE_1 but rose->neighbour == NULL.
When the socket is subsequently closed, rose_release() sees
ROSE_STATE_1 and calls rose_write_internal() ->
rose_transmit_link(skb, NULL), causing a NULL pointer dereference.

Per connect(2), a second connect() while a connection is already in
progress should return -EALREADY. Add this missing check for
TCP_SYN_SENT to complete the state validation in rose_connect().

[1] https://syzkaller.appspot.com/bug?extid=d00f90e0af54102fb271
[2] https://gist.github.com/mrpre/9e6779e0d13e2c66779b1653fef80516

## Affected

- `linux_kernel >= 2.6.12.1, < 5.10.253`
- `linux_kernel >= 5.11, < 5.15.203`
- `linux_kernel >= 5.16, < 6.1.167`
- `linux_kernel >= 6.2, < 6.6.130`
- `linux_kernel >= 6.7, < 6.12.78`
- `linux_kernel >= 6.13, < 6.18.20`
- `linux_kernel >= 6.19, < 6.19.10`
- `linux_kernel = 2.6.12`
- `linux_kernel = 7.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.19.10`