CVE-2026-74533

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/876a3e94c70d0859d1dad1c986112d4f0d99eba8
https://git.kernel.org/stable/c/af24e338bf5dafb80f42baa9a0b9e9b57b1c5d9c

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 13:17

Updated : 2026-08-17 06:19

NVD link : CVE-2026-74533

Mitre link : CVE-2026-74533

CVE.ORG link : CVE-2026-74533

JSON object : View

Products Affected

No product.

CWE

No CWE.

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