CVE-2023-53016: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: Fix possible deadlock in rfcomm_sk_state_change syzbot reports a possible deadlock in rfcomm_sk_state_change [1]. While rfcomm_sock_connect acquires the sk lock and waits for the rfcomm lock, rfcomm_sock_release could have the rfcomm lock and hit a deadlock for acquiring the sk lock. Here's a simplified flow: rfcomm_sock_connect: lock_sock(sk) rfcomm_dlc_open: rfcomm_lock() rfcomm_sock_release: rfcomm_sock_shutdown: rfcomm_lock() __rfcomm_dlc_close: rfcomm_k_state_change: lock_sock(sk) This patch drops the sk lock before calling rfcomm_dlc_open to avoid the possible deadlock and holds sk's reference count to prevent use-after-free after rfcomm_dlc_open completes.

Affected products

• Linux Linux Kernel: from 5.15, before 5.15.91 (fixed in 5.15.91); from 5.16, before 6.1.9 (fixed in 6.1.9); version 6.2 only

Published 2025-03-27. Last modified 2026-06-17.