CVE-2026-74534

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix refcounting of iso_conn iso_conn_del() and iso_chan_del() have a race that results to double-put of iso_conn: [Task hdev->workqueue] [Task 2] iso_conn_del iso_chan_del iso_conn_hold_unless_zero iso_conn_lock iso_conn_lock conn->sk = NULL iso_conn_unlock sk = iso_sock_hold(conn) <---------´ if (!sk) iso_conn_put iso_conn_put iso_conn_put /* UAF */ The extra put for !sk in iso_conn_del() is currently required since failing iso_chan_add() may leave iso_conn not associated with any sk. Fix by having iso_pi(sk)->conn own refcount when non-NULL, so iso_conn_del does not need to put it. Adjust the iso_conn_add() refcounting so that conn is put if it does not get associated with an sk.

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/3b921533e8aa95b77aadcf31737595578e735f3c
https://git.kernel.org/stable/c/8208b4939afb0a1977fffe902c3ca42fe0f3baaa
https://git.kernel.org/stable/c/fdfde532ab1caa165fcd8985001157ac8b4db365

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 13:17

Updated : 2026-08-17 06:19

NVD link : CVE-2026-74534

Mitre link : CVE-2026-74534

CVE.ORG link : CVE-2026-74534

JSON object : View

Products Affected

No product.

CWE

No CWE.

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