CVE-2026-90256

high

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind hci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via hci_conn_timeout (disc_work) -> hci_proto_disconn_ind -> l2cap_disconn_ind. This is UAF if the l2cap_conn is deleted concurrently. disc_work is disabled sync in hci_conn_del(), so we cannot take hci_dev_lock in disc_work. Fix by using proto_lock to guard l2cap_data, in addition to hdev->lock which is held in other access paths.

References

https://git.kernel.org/stable/c/b495a3a9b33bc4e4613e685bf5c96c136caa22d8

https://git.kernel.org/stable/c/2b66c83ff1751d6bd3201b3017206262ab46dc05

Details

Source: Mitre, NVD

Published: 2026-09-17

Updated: 2026-09-17

Risk Information

CVSS v2

Base Score: 5.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 7.1

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Severity: High