CVE-2026-74540

Source
https://cve.org/CVERecord?id=CVE-2026-74540
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74540.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-74540
Downstream
Published
2026-08-15T12:27:51Z
Modified
2026-08-21T03:30:21Z
Severity
  • 8.8 (High) CVSS_V3 - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
Bluetooth: L2CAP: fix UAF in l2cap_le_connect_rsp
Details

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.

Database specific
{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74540.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
f1496dee9cbde2a62821f4441dadb0d3360f60c3
Fixed
15d6c2367217a6a20b1abae9f38ded716bf620f1
Fixed
1818180fe12d6cec7a437bc59cde8efdf6b10250
Fixed
8325eafb38c3dee5af329266393763693d17381b
Fixed
fd4c1e301bdec60a40728ea37de531cbccda501a
Fixed
522b730c62c53a1981604fd73524697fd347830d
Fixed
58e3c5289ad230a7e24ae4b0c7b43f5ee6e32136
Fixed
09f447accc2570751e7d17f0dc0788b40d3edade
Fixed
c4740e7f23ff9a8210198d8b4703259e21b9f69d

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74540.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
3.14.0
Fixed
5.10.265
Type
ECOSYSTEM
Events
Introduced
5.11.0
Fixed
5.15.216
Type
ECOSYSTEM
Events
Introduced
5.16.0
Fixed
6.1.183
Type
ECOSYSTEM
Events
Introduced
6.2.0
Fixed
6.6.151
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.12.103
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
6.18.44
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.1.8

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74540.json"