{"cve":"CVE-2025-40308","nvd":{"published":"2025-12-08T01:16:03.073","modified":"2026-10-14T22:10:00.210","status":"Deferred","description":"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 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.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/164586725b47f9d61912e6bf17dbaffeff11710b","https://git.kernel.org/stable/c/39a7d40314b6288cfa2d13269275e9247a7a055a","https://git.kernel.org/stable/c/55c1519fca830f59a10bbf9aa8209c87b06cf7bc","https://git.kernel.org/stable/c/799cd62cbcc3f12ee04b33ef390ff7d41c37d671","https://git.kernel.org/stable/c/8b892dbef3887dbe9afdc7176d1a5fd90e1636aa"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2025-40308","score":0.00195,"percentile":0.09154,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}