Not yet scoredPublished Dec 7, 2025

CVE-2025-40308Bluetooth: bcsp: receive data only if registered

Updated under an hour ago (Oct 26, 2026, 3:23 PM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: bcsp: receive data only if registered Currently, bcsp_recv() can be called even when the BCSP protocol has not been registered. This leads to a NULL pointer dereference, as shown in the following stack trace: KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f] RIP: 0010:bcsp_recv+0x13d/0x1740 drivers/bluetooth/hci_bcsp.c:590 Call Trace: <TASK> hci_uart_tty_receive+0x194/0x220 drivers/bluetooth/hci_ldisc.c:627 tiocsti+0x23c/0x2c0 drivers/tty/tty_io.c:2290 tty_ioctl+0x626/0xde0 drivers/tty/tty_io.c:2706 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f To prevent this, ensure that the HCI_UART_REGISTERED flag is set before processing received data. If the protocol is not registered, return -EUNATCH.

CVSS: Not yet scored
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Deferred
Record last updated: May 23, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	48effdb7a798232db945503cf3f51e0be8070cea builds before 39a7d40314b6288cfa2d13269275e9247a7a055a; from 45fa7bd82c6178f4fec0ab94891144a043ec5fe8 before 164586725b47f9d61912e6bf17dbaffeff11710b; from d71a57a34ab6bbc95dc461158403c02e8ff3f912 before b65ca9708bfbf47d8b7bd44b7c574bd16798e9c9; 9cf7dccaa7f4c56d2089700e5cb11f85a8d5f6cf builds before 8b892dbef3887dbe9afdc7176d1a5fd90e1636aa; 806464634e7fc6b523160defeeddb1ade2a72f81 builds before 799cd62cbcc3f12ee04b33ef390ff7d41c37d671; from 6b7a32fa9bacdebd98c18b2a56994116995ee643 before b420a4c7f915fc1c94ad1f6ca740acc046d94334; 366ceff495f902182d42b6f41525c2474caf3f9a builds before 55c1519fca830f59a10bbf9aa8209c87b06cf7bc; from 366ceff495f902182d42b6f41525c2474caf3f9a before ca94b2b036c22556c3a66f1b80f490882deef7a6; and 10 more ranges	CNA record

References

References

https://git.kernel.org/stable/c/39a7d40314b6288cfa2d13269275e9247a7a055a
https://git.kernel.org/stable/c/164586725b47f9d61912e6bf17dbaffeff11710b
https://git.kernel.org/stable/c/b65ca9708bfbf47d8b7bd44b7c574bd16798e9c9
https://git.kernel.org/stable/c/8b892dbef3887dbe9afdc7176d1a5fd90e1636aa
https://git.kernel.org/stable/c/799cd62cbcc3f12ee04b33ef390ff7d41c37d671
https://git.kernel.org/stable/c/b420a4c7f915fc1c94ad1f6ca740acc046d94334
https://git.kernel.org/stable/c/55c1519fca830f59a10bbf9aa8209c87b06cf7bc
https://git.kernel.org/stable/c/ca94b2b036c22556c3a66f1b80f490882deef7a6

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.