CVEvulnerability
CVE-2026-74540
8.8 HIGH
Official page ↗
- Status
- Received
- Published
- 2026-08-15
- Last modified
- 2026-10-16
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 8.8 HIGH — CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: fix UAF in l2cap_le_connect_rsp
l2cap_le_connect_rsp() obtains a channel via
__l2cap_get_chan_by_ident() but neither holds a reference nor uses
l2cap_chan_hold_unless_zero() before locking and operating on it.
A concurrent l2cap_chan_del() triggered by a remote disconnect can
free the channel between the lookup and l2cap_chan_lock(), causing
a use-after-free.
The BR/EDR counterpart l2cap_connect_rsp() and the sibling handler
l2cap_le_command_rej() already use l2cap_chan_hold_unless_zero()
to safely hold a reference, but l2cap_le_connect_rsp() was left
unprotected.
Fix by adding l2cap_chan_hold_unless_zero() after the ident lookup
and l2cap_chan_put() on the exit path, consistent with other L2CAP
response handlers.
References
- https://git.kernel.org/stable/c/09f447accc2570751e7d17f0dc0788b40d3edade git.kernel.org
- https://git.kernel.org/stable/c/15d6c2367217a6a20b1abae9f38ded716bf620f1 git.kernel.org
- https://git.kernel.org/stable/c/1818180fe12d6cec7a437bc59cde8efdf6b10250 git.kernel.org
- https://git.kernel.org/stable/c/522b730c62c53a1981604fd73524697fd347830d git.kernel.org
- https://git.kernel.org/stable/c/58e3c5289ad230a7e24ae4b0c7b43f5ee6e32136 git.kernel.org
- https://git.kernel.org/stable/c/8325eafb38c3dee5af329266393763693d17381b git.kernel.org
- https://git.kernel.org/stable/c/c4740e7f23ff9a8210198d8b4703259e21b9f69d git.kernel.org
- https://git.kernel.org/stable/c/fd4c1e301bdec60a40728ea37de531cbccda501a git.kernel.org