CVE-2026-74534 (GCVE-0-2026-74534)
Vulnerability from cvelistv5
Published
2026-08-15 12:27
Modified
2026-10-23 08:20
Severity ?
8.8 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: a58d0f5dac322e16cc75334d000666512341bde5
Version: dc26097bdb864a0d5955b9a25e43376ffc1af99b
Version: dc26097bdb864a0d5955b9a25e43376ffc1af99b
Version: dc26097bdb864a0d5955b9a25e43376ffc1af99b
Version: f53e7489273dc2bb307bf50f319b3762d45534f0
Version: 6.12.2   ≤
Version: 6.11.11   ≤
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