CVE-2026-74534: Linux

High severity, CVSS 8.8. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Linux Linux: from 6.11.11, before 6.12 (fixed in 6.12); from 6.12.2, before 6.13 (fixed in 6.13); from 6.13, before 6.18.44 (fixed in 6.18.44); from 6.19, before 7.1.8 (fixed in 7.1.8)

Published 2026-08-15. Last modified 2026-08-17.