---
id: CVE-2026-53256
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()

  rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,
  but returns the selected listene…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()

  rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,
  but returns the selected listene…
severity: high
cvss: 8
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.12.1, < 5.10.259'
  - 'linux_kernel >= 5.11, < 5.15.210'
  - 'linux_kernel >= 5.16, < 6.1.176'
  - 'linux_kernel >= 6.2, < 6.6.143'
  - 'linux_kernel >= 6.7, < 6.12.94'
  - 'linux_kernel >= 6.13, < 6.18.36'
  - 'linux_kernel >= 6.19, < 7.0.13'
  - linux_kernel = 2.6.12
  - linux_kernel = 7.1
patched:
  - linux_kernel 7.0.13
published: '2026-06-25'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:20:07.473'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53256'
references:
  - url: 'https://git.kernel.org/stable/c/1f73f92f66251065a5f39b09a47cf05ea14d3107'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/43c441edacf953b39517a44f5e5e10a93618b226'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6f4462d12133106460d7c046b95aad2491e3fddf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8802413ce63175fb522a2bd609fb043a3550c720'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a07d741c077d4e34b16458241a94d29039386553'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b0e33e409715c617e2a20f46f99aa5403a14dfda'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/de31973ef00e5aa55496f84cf6a44bb157a34e02'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f5ec76bdbeb80f75ad0be204371afffee0f8fac8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-784472.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00248
epssPercentile: 0.14971
ingestedAt: '2026-10-15T03:30:12.911Z'
---

## Overview

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

Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()

rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,
but returns the selected listener after dropping that lock without
taking a reference. rfcomm_connect_ind() then locks the listener,
queues a child socket on it, and may notify it after unlocking it.

The buggy scenario involves two paths, with each column showing the
order within that path:

rfcomm_connect_ind():            listener close:
  1. Find parent in              1. close() enters
     rfcomm_get_sock_by_channel()   rfcomm_sock_release().
  2. Drop rfcomm_sk_list.lock    2. rfcomm_sock_shutdown()
     without pinning parent.        closes the listener.
  3. Call lock_sock(parent) and  3. rfcomm_sock_kill()
     bt_accept_enqueue(parent,      unlinks and puts parent.
     sk, true).
  4. Read parent flags and may   4. parent can be freed.
     call sk_state_change().

If close wins the race, parent can be freed before
rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the
deferred-setup callback.

Take a reference on the listener before leaving rfcomm_sk_list.lock.
After lock_sock() succeeds, recheck that it is still in BT_LISTEN
before queueing a child, cache the deferred-setup bit while the parent
is locked, and drop the reference after the last parent use.

KASAN reported a slab-use-after-free in lock_sock_nested() from
rfcomm_connect_ind(), with the freeing stack going through
rfcomm_sock_kill() and rfcomm_sock_release().

## Affected

- `linux_kernel >= 2.6.12.1, < 5.10.259`
- `linux_kernel >= 5.11, < 5.15.210`
- `linux_kernel >= 5.16, < 6.1.176`
- `linux_kernel >= 6.2, < 6.6.143`
- `linux_kernel >= 6.7, < 6.12.94`
- `linux_kernel >= 6.13, < 6.18.36`
- `linux_kernel >= 6.19, < 7.0.13`
- `linux_kernel = 2.6.12`
- `linux_kernel = 7.1`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.13`