---
id: CVE-2025-39827
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: rose: include node references in rose_neigh refcount

  Current implementation maintains two separate reference counting
  mechanisms: the 'count' field in struct rose…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: rose: include node references in rose_neigh refcount

  Current implementation maintains two separate reference counting
  mechanisms: the 'count' field in struct rose…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.12.1, < 6.1.150'
  - 'linux_kernel >= 6.2, < 6.6.104'
  - 'linux_kernel >= 6.7, < 6.12.45'
  - 'linux_kernel >= 6.13, < 6.16.5'
  - linux_kernel = 2.6.12
  - linux_kernel = 6.17
  - debian_linux = 11.0
patched:
  - linux_kernel 6.16.5
published: '2025-09-16'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:18:01.717'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-39827'
references:
  - url: 'https://git.kernel.org/stable/c/384210cceb1873a4c8218b27ba0745444436b728'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4cce478c3e82a5fc788d72adb2f4c4e983997639'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9c547c8eee9d1cf6e744611d688b9f725cf9a115'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d7563b456ed44151e1a82091d96f60166daea89b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/da9c9c877597170b929a6121a68dcd3dd9a80f45'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-032379.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-457936.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00225
epssPercentile: 0.13139
ingestedAt: '2026-09-08T15:33:26.996Z'
---

## Overview

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

net: rose: include node references in rose_neigh refcount

Current implementation maintains two separate reference counting
mechanisms: the 'count' field in struct rose_neigh tracks references from
rose_node structures, while the 'use' field (now refcount_t) tracks
references from rose_sock.

This patch merges these two reference counting systems using 'use' field
for proper reference management. Specifically, this patch adds incrementing
and decrementing of rose_neigh->use when rose_neigh->count is incremented
or decremented.

This patch also modifies rose_rt_free(), rose_rt_device_down() and
rose_clear_route() to properly release references to rose_neigh objects
before freeing a rose_node through rose_remove_node().

These changes ensure rose_neigh structures are properly freed only when
all references, including those from rose_node structures, are released.
As a result, this resolves a slab-use-after-free issue reported by Syzbot.

## Affected

- `linux_kernel >= 2.6.12.1, < 6.1.150`
- `linux_kernel >= 6.2, < 6.6.104`
- `linux_kernel >= 6.7, < 6.12.45`
- `linux_kernel >= 6.13, < 6.16.5`
- `linux_kernel = 2.6.12`
- `linux_kernel = 6.17`
- `debian_linux = 11.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.16.5`