---
id: CVE-2026-53072
title: 'Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER

  When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls
  hci_connect_cfm(conn) without hd…
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'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    60e3f4ff02d1f2d55bfbf2ca32a97285a9771ee4
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    9d4a6c0f43fc5e4d4f062e8e450e5483eb74176e
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    c7777f534a8018ae4bb1c80d8925af4df588a314
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    6b4d226d01ab7da0d2027a2a1e3a6079152e5065
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    541d5bf9b5afaf41090b2a3aa7b47f2db2ff801f
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    385b2d0468a0871fc716c549fa3b0c257c7dbcb3
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    c27224daf0b08efbb2b24ed64b6139b294f5473a
  - >-
    Linux >= 70c464256310e1c3716099b9d02ece4169272f73 <
    5c7209a341ff2ac338b2b0375c34a307b37c9ac2
  - Linux 3.17
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:25:12.695617Z'
published: '2026-06-24'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:31:30.673Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-53072'
references:
  - url: 'https://git.kernel.org/stable/c/60e3f4ff02d1f2d55bfbf2ca32a97285a9771ee4'
  - url: 'https://git.kernel.org/stable/c/9d4a6c0f43fc5e4d4f062e8e450e5483eb74176e'
  - url: 'https://git.kernel.org/stable/c/c7777f534a8018ae4bb1c80d8925af4df588a314'
  - url: 'https://git.kernel.org/stable/c/6b4d226d01ab7da0d2027a2a1e3a6079152e5065'
  - url: 'https://git.kernel.org/stable/c/541d5bf9b5afaf41090b2a3aa7b47f2db2ff801f'
  - url: 'https://git.kernel.org/stable/c/385b2d0468a0871fc716c549fa3b0c257c7dbcb3'
  - url: 'https://git.kernel.org/stable/c/c27224daf0b08efbb2b24ed64b6139b294f5473a'
  - url: 'https://git.kernel.org/stable/c/5c7209a341ff2ac338b2b0375c34a307b37c9ac2'
tags:
  - cve.org
epss: 0.00195
epssPercentile: 0.08574
ingestedAt: '2026-10-16T17:24:46.729Z'
---

## Overview

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

Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER

When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls
hci_connect_cfm(conn) without hdev->lock. Generally hci_connect_cfm()
assumes it is held, and if conn is deleted concurrently -> UAF.

Only SCO and ISO set HCI_PROTO_DEFER and only for defer setup listen,
and HCI_EV_CONN_REQUEST is not generated for ISO.  In the non-deferred
listening socket code paths, hci_connect_cfm(conn) is called with
hdev->lock held.

Fix by holding the lock.

## Affected

- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < 60e3f4ff02d1f2d55bfbf2ca32a97285a9771ee4`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < 9d4a6c0f43fc5e4d4f062e8e450e5483eb74176e`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < c7777f534a8018ae4bb1c80d8925af4df588a314`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < 6b4d226d01ab7da0d2027a2a1e3a6079152e5065`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < 541d5bf9b5afaf41090b2a3aa7b47f2db2ff801f`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < 385b2d0468a0871fc716c549fa3b0c257c7dbcb3`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < c27224daf0b08efbb2b24ed64b6139b294f5473a`
- `Linux >= 70c464256310e1c3716099b9d02ece4169272f73 < 5c7209a341ff2ac338b2b0375c34a307b37c9ac2`
- `Linux 3.17`

## Remediation

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