{"id":"CVE-2025-40308","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: bcsp: receive data only if registered\n\nCurrently, bcsp_recv() can be called even when the BCSP protocol has not\nbeen registered","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: bcsp: receive data only if registered\n\nCurrently, bcsp_recv() can be called even when the BCSP protocol has not\nbeen registered. This leads to a NULL pointer…","severity":"none","published":"2025-12-08","updated":"2026-10-14","sourceUpdated":"2026-10-14T22:10:00.210","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-40308","references":[{"url":"https://git.kernel.org/stable/c/164586725b47f9d61912e6bf17dbaffeff11710b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/39a7d40314b6288cfa2d13269275e9247a7a055a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/55c1519fca830f59a10bbf9aa8209c87b06cf7bc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/799cd62cbcc3f12ee04b33ef390ff7d41c37d671","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8b892dbef3887dbe9afdc7176d1a5fd90e1636aa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b420a4c7f915fc1c94ad1f6ca740acc046d94334","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b65ca9708bfbf47d8b7bd44b7c574bd16798e9c9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ca94b2b036c22556c3a66f1b80f490882deef7a6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00195,"epssPercentile":0.08603,"ingestedAt":"2026-10-14T23:00:02.020Z","slug":"CVE-2025-40308","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: bcsp: receive data only if registered\n\nCurrently, bcsp_recv() can be called even when the BCSP protocol has not\nbeen registered. This leads to a NULL pointer dereference, as shown in\nthe following stack trace:\n\n    KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]\n    RIP: 0010:bcsp_recv+0x13d/0x1740 drivers/bluetooth/hci_bcsp.c:590\n    Call Trace:\n     <TASK>\n     hci_uart_tty_receive+0x194/0x220 drivers/bluetooth/hci_ldisc.c:627\n     tiocsti+0x23c/0x2c0 drivers/tty/tty_io.c:2290\n     tty_ioctl+0x626/0xde0 drivers/tty/tty_io.c:2706\n     vfs_ioctl fs/ioctl.c:51 [inline]\n     __do_sys_ioctl fs/ioctl.c:907 [inline]\n     __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893\n     do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n     do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94\n     entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nTo prevent this, ensure that the HCI_UART_REGISTERED flag is set before\nprocessing received data. If the protocol is not registered, return\n-EUNATCH.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}