{"id":"CVE-2026-98109","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: Fix race condition during device registration\n\nIn hci_register_dev(), the power_on work item is queued to\nhdev->req_workqueue before initializing h…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: Fix race condition during device registration\n\nIn hci_register_dev(), the power_on work item is queued to\nhdev->req_workqueue before initializing h…","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-362","CWE-908"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 6.4.16, < 6.5","linux_kernel >= 6.5.3, < 6.12.111","linux_kernel >= 6.13, < 6.18.53","linux_kernel >= 6.19, < 7.2.7","linux_kernel = 7.3"],"patched":["linux_kernel 7.2.7"],"published":"2026-09-25","updated":"2026-10-03","sourceUpdated":"2026-10-03T11:18:32.990","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98109","references":[{"url":"https://git.kernel.org/stable/c/57938bbdb9bf7fd41cbd5cd509ec10c4b22bec18","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/593e64f64a20b25e4042c3ee863119eb7f991785","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a11ebe8dc0333fb870bbbb656b34690e87ee3f98","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b1faf348c29e6f8302ec7769cbf1c1ef05be014f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d427b1c71d9798083e954d3c13469dc0a2305868","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98109.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98109"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541338"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98109"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98109"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98109.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00089,"epssPercentile":0.00389,"scores":{"nvd":4.7,"vendor":5.5},"ingestedAt":"2026-09-25T11:06:38.824Z","slug":"CVE-2026-98109","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: Fix race condition during device registration\n\nIn hci_register_dev(), the power_on work item is queued to\nhdev->req_workqueue before initializing hdev->adv_monitors_idr and\nregistering the MSFT extension via msft_register(). For devices marked with\nquirks such as HCI_QUIRK_RAW_DEVICE, the HCI_UNCONFIGURED flag is set on\nthe device. When the power_on work item runs concurrently on another CPU,\nhci_power_on() detects that the device is unconfigured and immediately\ninvokes hci_dev_do_close(), which calls msft_do_close().\n\nConcurrently, msft_register() allocates the msft structure and exposes it\nto hdev->msft_data prior to calling mutex_init(&msft->filter_lock). If\nmsft_do_close() executes while hdev->msft_data is already assigned but the\nmutex has not yet been initialized, mutex_lock(&msft->filter_lock) operates\non an uninitialized mutex, triggering a DEBUG_LOCKS warning:\n\nDEBUG_LOCKS_WARN_ON(lock->magic != lock)\nWARNING: kernel/locking/mutex.c:625 at __mutex_lock_common\nkernel/locking/mutex.c:625 [inline]\nWARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x12d8/0x1550\nkernel/locking/mutex.c:821\n...\nCall Trace:\n <TASK>\n msft_do_close+0x308/0x7b0 net/bluetooth/msft.c:693\n hci_dev_close_sync+0x86b/0x10a0 net/bluetooth/hci_sync.c:5522\n hci_dev_do_close net/bluetooth/hci_core.c:499 [inline]\n hci_power_on+0x32c/0x750 net/bluetooth/hci_core.c:937\n process_one_work kernel/workqueue.c:3322 [inline]\n process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405\n worker_thread+0x92d/0xe10 kernel/workqueue.c:3486\n kthread+0x388/0x470 kernel/kthread.c:436\n ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n </TASK>\n\nFix this by moving the queue_work() call in hci_register_dev() to after\nidr_init(&hdev->adv_monitors_idr) and msft_register(hdev) so that device\nstructures and extensions are fully initialized before asynchronous tasks\ncan access them. Additionally, assign hdev->msft_data in msft_register()\nonly after mutex_init(&msft->filter_lock) has completed.\n\n## Affected\n\n- `linux_kernel >= 6.4.16, < 6.5`\n- `linux_kernel >= 6.5.3, < 6.12.111`\n- `linux_kernel >= 6.13, < 6.18.53`\n- `linux_kernel >= 6.19, < 7.2.7`\n- `linux_kernel = 7.3`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.2.7`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98109.json)","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":214952,"id":"CVE-2026-98109","ts":1790954530354,"field":"cvss","old":null,"new":"4.7"},{"seq":214951,"id":"CVE-2026-98109","ts":1790954530354,"field":"severity","old":"none","new":"medium"}]}