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

Bluetooth: L2CAP: access chan->conn safely in get/setsockopt

Since commit b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref")
l2cap_chan::conn has held reference and remains non-NULL also after the
corresponding hci_conn is deleted. In this state accessing various
fields eg. hci_conn::hdev is invalid, which leads to KASAN crash in
l2cap_sock_setsockopt() access of conn->hcon->hdev.

Check l2cap_chan::conn.hcon corresponds to an alive hci_conn before
trying to use it in l2cap_sock.c. Hold l2cap_chan_lock() in
getsockopt/setsockopt to ensure it stays alive, and to avoid data races
in l2cap_chan fields.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 30 Oct 2026 12:45:00 +0000


Wed, 21 Oct 2026 13:15:00 +0000


Thu, 15 Oct 2026 13:30:00 +0000


Sun, 20 Sep 2026 04:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Fri, 18 Sep 2026 21:30:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Thu, 17 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: access chan->conn safely in get/setsockopt Since commit b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref") l2cap_chan::conn has held reference and remains non-NULL also after the corresponding hci_conn is deleted. In this state accessing various fields eg. hci_conn::hdev is invalid, which leads to KASAN crash in l2cap_sock_setsockopt() access of conn->hcon->hdev. Check l2cap_chan::conn.hcon corresponds to an alive hci_conn before trying to use it in l2cap_sock.c. Hold l2cap_chan_lock() in getsockopt/setsockopt to ensure it stays alive, and to avoid data races in l2cap_chan fields.
Title Bluetooth: L2CAP: access chan->conn safely in get/setsockopt
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-30T12:34:05.630Z

Reserved: 2026-09-11T19:38:34.786Z

Link: CVE-2026-90093

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-17T17:17:00.900

Modified: 2026-10-30T13:20:41.080

Link: CVE-2026-90093

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-20T04:30:18Z

Weaknesses