CVE-2022-50166
Status: AnalyzedMedium (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: When HCI work queue is drained, only queue chained work
The HCI command, event, and data packet processing workqueue is drained to avoid deadlock in commit 76727c02c1e1 ("Bluetooth: Call drain_workqueue() before resetting state").
There is another delayed work, which will queue command to this drained workqueue. Which results in the following error report:
To fix this, we can add a new HCI_DRAIN_WQ flag, and don't queue the timeout workqueue while command workqueue is draining.
Technical details traces, logs and code from the original report
Bluetooth: hci2: command 0x040f tx timeout WARNING: CPU: 1 PID: 18374 at kernel/workqueue.c:1438 __queue_work+0xdad/0x1140 Workqueue: events hci_cmd_timeout RIP: 0010:__queue_work+0xdad/0x1140 RSP: 0000:ffffc90002cffc60 EFLAGS: 00010093 RAX: 0000000000000000 RBX: ffff8880b9d3ec00 RCX: 0000000000000000 RDX: ffff888024ba0000 RSI: ffffffff814e048d RDI: ffff8880b9d3ec08 RBP: 0000000000000008 R08: 0000000000000000 R09: 00000000b9d39700 R10: ffffffff814f73c6 R11: 0000000000000000 R12: ffff88807cce4c60 R13: 0000000000000000 R14: ffff8880796d8800 R15: ffff8880796d8800 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0174b4000 CR3: 000000007cae9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? queue_work_on+0xcb/0x110 ? lockdep_hardirqs_off+0x90/0xd0 queue_work_on+0xee/0x110 process_one_work+0x996/0x1610 ? pwq_dec_nr_in_flight+0x2a0/0x2a0 ? rwlock_bug.part.0+0x90/0x90 ? _raw_spin_lock_irq+0x41/0x50 worker_thread+0x665/0x1080 ? process_one_work+0x1610/0x1610 kthread+0x2e9/0x3a0 ? kthread_complete_and_exit+0x40/0x40 ret_from_fork+0x1f/0x30 </TASK>
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Base score: 5.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.18%
- Percentile among all scored CVEs: 7
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- CWE-667
References
Raw JSON (NVD)
Show
{
"id": "CVE-2022-50166",
"cveTags": [],
"metrics": {
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"type": "Primary",
"source": "nvd@nist.gov",
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"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
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"net/bluetooth/hci_core.c",
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"published": "2025-06-18T11:15:46.907",
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"descriptions": [
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: When HCI work queue is drained, only queue chained work\n\nThe HCI command, event, and data packet processing workqueue is drained\nto avoid deadlock in commit\n76727c02c1e1 (\"Bluetooth: Call drain_workqueue() before resetting state\").\n\nThere is another delayed work, which will queue command to this drained\nworkqueue. Which results in the following error report:\n\nBluetooth: hci2: command 0x040f tx timeout\nWARNING: CPU: 1 PID: 18374 at kernel/workqueue.c:1438 __queue_work+0xdad/0x1140\nWorkqueue: events hci_cmd_timeout\nRIP: 0010:__queue_work+0xdad/0x1140\nRSP: 0000:ffffc90002cffc60 EFLAGS: 00010093\nRAX: 0000000000000000 RBX: ffff8880b9d3ec00 RCX: 0000000000000000\nRDX: ffff888024ba0000 RSI: ffffffff814e048d RDI: ffff8880b9d3ec08\nRBP: 0000000000000008 R08: 0000000000000000 R09: 00000000b9d39700\nR10: ffffffff814f73c6 R11: 0000000000000000 R12: ffff88807cce4c60\nR13: 0000000000000000 R14: ffff8880796d8800 R15: ffff8880796d8800\nFS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 000000c0174b4000 CR3: 000000007cae9000 CR4: 00000000003506e0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n <TASK>\n ? queue_work_on+0xcb/0x110\n ? lockdep_hardirqs_off+0x90/0xd0\n queue_work_on+0xee/0x110\n process_one_work+0x996/0x1610\n ? pwq_dec_nr_in_flight+0x2a0/0x2a0\n ? rwlock_bug.part.0+0x90/0x90\n ? _raw_spin_lock_irq+0x41/0x50\n worker_thread+0x665/0x1080\n ? process_one_work+0x1610/0x1610\n kthread+0x2e9/0x3a0\n ? kthread_complete_and_exit+0x40/0x40\n ret_from_fork+0x1f/0x30\n </TASK>\n\nTo fix this, we can add a new HCI_DRAIN_WQ flag, and don't queue the\ntimeout workqueue while command workqueue is draining."
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: Bluetooth: Al vaciar la cola de trabajo de HCI, solo se pone en cola el trabajo encadenado. La cola de trabajo de procesamiento de comandos, eventos y paquetes de datos de HCI se vacía para evitar un bloqueo en el commit 76727c02c1e1 (\"Bluetooth: Llamar a drain_workqueue() antes de restablecer el estado\"). Existe otro trabajo retrasado que pondrá en cola el comando en esta cola de trabajo vaciada. Lo que genera el siguiente informe de error: Bluetooth: hci2: command 0x040f tx timeout ADVERTENCIA: CPU: 1 PID: 18374 en kernel/workqueue.c:1438 __queue_work+0xdad/0x1140 Workqueue: events hci_cmd_timeout RIP: 0010:__queue_work+0xdad/0x1140 RSP: 0000:ffffc90002cffc60 EFLAGS: 00010093 RAX: 0000000000000000 RBX: ffff8880b9d3ec00 RCX: 0000000000000000 RDX: ffff888024ba0000 RSI: ffffffff814e048d RDI: ffff8880b9d3ec08 RBP: 0000000000000008 R08: 0000000000000000 R09: 00000000b9d39700 R10: ffffffff814f73c6 R11: 000000000000000 R12: ffff88807cce4c60 R13: 000000000000000 R14: ffff8880796d8800 R15: ffff8880796d8800 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0174b4000 CR3: 000000007cae9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Rastreo de llamadas: ? queue_work_on+0xcb/0x110 ? lockdep_hardirqs_off+0x90/0xd0 queue_work_on+0xee/0x110 process_one_work+0x996/0x1610 ? pwq_dec_nr_in_flight+0x2a0/0x2a0 ? rwlock_bug.part.0+0x90/0x90 ? _raw_spin_lock_irq+0x41/0x50 worker_thread+0x665/0x1080 ? process_one_work+0x1610/0x1610 kthread+0x2e9/0x3a0 ? kthread_complete_and_exit+0x40/0x40 ret_from_fork+0x1f/0x30 Para solucionar esto, podemos agregar un nuevo indicador HCI_DRAIN_WQ y no poner en cola la cola de trabajo de tiempo de espera mientras se drena la cola de trabajo de comandos."
}
],
"lastModified": "2026-06-17T05:22:53.700",
"configurations": [
{
"nodes": [
{
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