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

Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero

hci_conn::iso_data is accessed and modified without lock or RCU.
This leads to a race

[Task hdev->workqueue] [Task 2]
iso_recv iso_conn_put(conn)
conn = LOAD hcon->iso_data iso_conn_free(conn)
iso_conn_hold_unless_zero(conn) hcon->iso_data = NULL
kfree(conn)
kref_get_unless_zero(&conn->ref) /* UAF */

and also to races in iso_conn_add() vs. iso_conn_free().

Fix by adding spinlock hci_conn::proto_lock and using it to guard
hci_conn::iso_data.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 21 Aug 2026 20:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-362
CWE-416

Fri, 21 Aug 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-825
References
Metrics threat_severity

None

threat_severity

Moderate


Mon, 17 Aug 2026 15:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-362
CWE-416

Mon, 17 Aug 2026 12:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Mon, 17 Aug 2026 06:00:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}


Sat, 15 Aug 2026 16:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Sat, 15 Aug 2026 12:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero hci_conn::iso_data is accessed and modified without lock or RCU. This leads to a race [Task hdev->workqueue] [Task 2] iso_recv iso_conn_put(conn) conn = LOAD hcon->iso_data iso_conn_free(conn) iso_conn_hold_unless_zero(conn) hcon->iso_data = NULL kfree(conn) kref_get_unless_zero(&conn->ref) /* UAF */ and also to races in iso_conn_add() vs. iso_conn_free(). Fix by adding spinlock hci_conn::proto_lock and using it to guard hci_conn::iso_data.
Title Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero
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: 2026-08-17T05:48:22.228Z

Reserved: 2026-08-15T05:44:03.912Z

Link: CVE-2026-74533

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-15T13:17:58.603

Modified: 2026-08-17T06:19:50.230

Link: CVE-2026-74533

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-08-15T00:00:00Z

Links: CVE-2026-74533 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-08-21T22:15:04Z

Weaknesses