---
id: CVE-2025-21718
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: rose: fix timer races against user threads

  Rose timers only acquire the socket spinlock, without
  checking if the socket is owned by one user thread.

  Add a check …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: rose: fix timer races against user threads

  Rose timers only acquire the socket spinlock, without
  checking if the socket is owned by one user thread.

  Add a check …
severity: high
cvss: 7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-362
  - CWE-416
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.12, < 6.1.129'
  - 'linux_kernel >= 6.2, < 6.6.76'
  - 'linux_kernel >= 6.7, < 6.12.13'
  - 'linux_kernel >= 6.13, < 6.13.2'
patched:
  - linux_kernel 6.13.2
published: '2025-02-27'
updated: '2026-07-14'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-21718'
references:
  - url: 'https://git.kernel.org/stable/c/0d5bca3be27bfcf8f980f2fed49b6cbb7dafe4a1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/1409b45d4690308c502c6caf22f01c3c205b4717'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/1992fb261c90e9827cf5dc3115d89bb0853252c9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/51c128ba038cf1b79d605cbee325919b45ab95a5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/52f5aff33ca73b2c2fa93f40a3de308012e63cf4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/58051a284ac18a3bb815aac6289a679903ddcc3f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5de7665e0a0746b5ad7943554b34db8f8614a196'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f55c88e3ca5939a6a8a329024aed8f3d98eea8e4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2025/05/msg00030.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://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21718.json
  - url: 'https://access.redhat.com/security/cve/CVE-2025-21718'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2348527'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2025-21718'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2025-21718'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2025022646-CVE-2025-21718-d976@gregkh/T
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00171
epssPercentile: 0.05769
ingestedAt: '2026-07-14T13:36:55.383Z'
---

## Overview

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

net: rose: fix timer races against user threads

Rose timers only acquire the socket spinlock, without
checking if the socket is owned by one user thread.

Add a check and rearm the timers if needed.

BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x31d/0x360 net/rose/rose_timer.c:174
Read of size 2 at addr ffff88802f09b82a by task swapper/0/0

CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc5-syzkaller-00172-gd1bf27c4e176 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
  __dump_stack lib/dump_stack.c:94 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
  print_address_description mm/kasan/report.c:378 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:489
  kasan_report+0x143/0x180 mm/kasan/report.c:602
  rose_timer_expiry+0x31d/0x360 net/rose/rose_timer.c:174
  call_timer_fn+0x187/0x650 kernel/time/timer.c:1793
  expire_timers kernel/time/timer.c:1844 [inline]
  __run_timers kernel/time/timer.c:2418 [inline]
  __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2430
  run_timer_base kernel/time/timer.c:2439 [inline]
  run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449
  handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
  __do_softirq kernel/softirq.c:595 [inline]
  invoke_softirq kernel/softirq.c:435 [inline]
  __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>

## Affected

- `linux_kernel >= 2.6.12, < 6.1.129`
- `linux_kernel >= 6.2, < 6.6.76`
- `linux_kernel >= 6.7, < 6.12.13`
- `linux_kernel >= 6.13, < 6.13.2`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.13.2`

## Vendor advisories

- **Red Hat VEX** · Important · updated 2026-09-13 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21718.json)