{"cve":"CVE-2026-64433","nvd":{"published":"2026-07-25T10:17:27.567","modified":"2026-09-03T18:26:49.233","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: MGMT: Fix UAF of hci_conn_params in add_device_complete\n\nadd_device_complete() runs from the hci_cmd_sync_work kworker, which\nholds only hci_req_sync_lock and *not* hci_dev_lock.  It calls\nhci_conn_params_lookup() and then dereferences the returned object\n(params->flags) without taking hci_dev_lock:\n\n\tparams = hci_conn_params_lookup(hdev, &cp->addr.bdaddr,\n\t\t\t\t\tle_addr_type(cp->addr.type));\n\t...\n\tdevice_flags_changed(NULL, hdev, &cp->addr.bdaddr,\n\t\t\t     cp->addr.type, hdev->conn_flags,\n\t\t\t     params ? params->flags : 0);\n\nhci_conn_params_lookup() walks hdev->le_conn_params and is documented to\nrequire hdev->lock.  A concurrent MGMT_OP_REMOVE_DEVICE\n(remove_device()), which does run under hci_dev_lock, can call\nhci_conn_params_free() to list_del() and kfree() the very object the\nlookup returned, so the subsequent params->flags read touches freed\nmemory [0].\n\nHold hci_dev_lock() across the hci_conn_params_lookup() and the read of\nparams->flags (and the matching event emission) so the lookup result\ncannot be freed by a concurrent remove_device() before it is used,\nhonouring the locking contract of hci_conn_params_lookup().\n\n[0]: (trailing page/memory-state dump trimmed)\nBUG: KASAN: slab-use-after-free in add_device_complete+0x358/0x3d8 net/bluetooth/mgmt.c:7671\nRead of size 1 at addr ffff000017ab26c1 by task kworker/u9:8/388\n\nCPU: 1 UID: 0 PID: 388 Comm: kworker/u9:8 Not tainted 7.0.11 #20 PREEMPT\nHardware name: linux,dummy-virt (DT)\nWorkqueue: hci0 hci_cmd_sync_work\nCall trace:\n show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0xb4/0xd4 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:378 [inline]\n print_report+0x118/0x5d8 mm/kasan/report.c:482\n kasan_report+0xb0/0xf4 mm/kasan/report.c:595\n __asan_report_load1_noabort+0x20/0x2c mm/kasan/report_generic.c:378\n add_device_complete+0x358/0x3d8 net/bluetooth/mgmt.c:7671\n hci_cmd_sync_work+0x14c/0x240 net/bluetooth/hci_sync.c:334\n process_one_work+0x628/0xd38 kernel/workqueue.c:3289\n process_scheduled_works kernel/workqueue.c:3372 [inline]\n worker_thread+0x7a8/0xac0 kernel/workqueue.c:3453\n kthread+0x39c/0x444 kernel/kthread.c:436\n ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860\n\nAllocated by task 3401:\n kasan_save_stack+0x3c/0x64 mm/kasan/common.c:57\n kasan_save_track+0x20/0x3c mm/kasan/common.c:78\n kasan_save_alloc_info+0x40/0x54 mm/kasan/generic.c:570\n poison_kmalloc_redzone mm/kasan/common.c:398 [inline]\n __kasan_kmalloc+0xd4/0xd8 mm/kasan/common.c:415\n kasan_kmalloc include/linux/kasan.h:263 [inline]\n __kmalloc_cache_noprof+0x1b0/0x458 mm/slub.c:5385\n kmalloc_noprof include/linux/slab.h:950 [inline]\n kzalloc_noprof include/linux/slab.h:1188 [inline]\n hci_conn_params_add+0x10c/0x4b0 net/bluetooth/hci_core.c:2279\n hci_conn_params_set net/bluetooth/mgmt.c:5162 [inline]\n add_device+0x5b4/0xa54 net/bluetooth/mgmt.c:7755\n hci_mgmt_cmd net/bluetooth/hci_sock.c:1721 [inline]\n hci_sock_sendmsg+0x10b4/0x1dd0 net/bluetooth/hci_sock.c:1841\n sock_sendmsg_nosec net/socket.c:727 [inline]\n __sock_sendmsg+0xe0/0x128 net/socket.c:742\n sock_write_iter+0x250/0x390 net/socket.c:1195\n new_sync_write fs/read_write.c:595 [inline]\n vfs_write+0x66c/0xab0 fs/read_write.c:688\n ksys_write+0x1fc/0x24c fs/read_write.c:740\n __do_sys_write fs/read_write.c:751 [inline]\n __se_sys_write fs/read_write.c:748 [inline]\n __arm64_sys_write+0x70/0xa4 fs/read_write.c:748\n __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]\n invoke_syscall+0x84/0x2a8 arch/arm64/kernel/syscall.c:49\n el0_svc_common.constprop.0+0xe4/0x294 arch/arm64/kernel/syscall.c:132\n do_el0_svc+0x44/0x5c arch/arm64/kernel/syscall.c:151\n el0_svc+0x38/0xac arch/arm64/kernel/entry-common.c:724\n el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:743\n el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596\n\nFreed by task 3740:\n kasan_save_stack+0x3c/0x64 \n---truncated---","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/9531014c60c804e16099885d4a98aedcf31bce8d","https://git.kernel.org/stable/c/b346efa825b5e4386f19bc63f81141652d496ec4","https://git.kernel.org/stable/c/caed4a96d55757c139a899744657c032b6186665","https://git.kernel.org/stable/c/e4369e4e970f3fa4676b76be14c1d315c87f22b6","https://git.kernel.org/stable/c/fa85d985f614bc3feb343000f14a1072e99b0df1"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:46:40.600842820+00:00"},"epss":{"cve":"CVE-2026-64433","score":0.00125,"percentile":0.02183,"date":"2026-10-31"},"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."]}