CVE-2026-74535 (GCVE-0-2026-74535)
Vulnerability from cvelistv5
Published
2026-08-15 12:27
Modified
2026-10-16 19:05
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: avoid deadlocks in iso_sock_timeout iso_sock_timeout() takes lock_sock, so sync disabling the timer while holding that lock may deadlock. iso_sock_timeout() may also run concurrently with iso_conn_del(), which leads to UAF [Task 1] [Task hdev->workqueue] iso_sock_timeout iso_conn_del iso_conn_hold_unless_zero iso_chan_del `------------> iso_conn_put caller frees hcon iso_conn_put iso_conn_free conn->hcon->iso_data = NULL; /* UAF */ Fix the deadlock by removing the disable from the lock_sock sections. Move the timer from iso_conn to iso_pinfo to decouple it from iso_conn which may need to be freed in lock_sock section. Convert some of the clear_timer to disable_timer.
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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