CVE-2026-74302 (GCVE-0-2026-74302)
Vulnerability from cvelistv5
Published
2026-08-15 05:58
Modified
2026-08-17 05:45
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_core: Fix UAF in hci_unregister_dev()
hci_unregister_dev() does not disable cmd_timer and ncmd_timer
before the hci_dev structure is freed. If a timeout fires
during device teardown, the callback dereferences freed memory
(including the hdev->reset function pointer), leading to a
use-after-free.
Add disable_delayed_work_sync() calls alongside the existing
disable_work_sync() calls to ensure both timers are fully
quiesced before teardown proceeds.
References
| URL | Tags | |
|---|---|---|
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Version: 0d151a103775dd9645c78c97f77d6e2a5298d913 Version: 0d151a103775dd9645c78c97f77d6e2a5298d913 Version: 0d151a103775dd9645c78c97f77d6e2a5298d913 Version: 0d151a103775dd9645c78c97f77d6e2a5298d913 Version: 48542881997e17b49dc16b93fe910e0cfcf7a9f9 Version: 9cfc84b1d464cc024286f42a090718f9067b80ed Version: ddeda6ca5f218b668b560d90fc31ae469adbfd92 Version: d2ce562a5aff1dcd0c50d9808ea825ef90da909f Version: 96600c2e5ee8213dbab5df1617293d8e847bb4fa Version: d6cbce18370641a21dd889e8613d8153df15eb39 Version: 3f939bd73fed12dddc2a32a76116c19ca47c7678 Version: 4.19.319 ≤ Version: 5.4.281 ≤ Version: 5.10.223 ≤ Version: 5.15.164 ≤ Version: 6.1.101 ≤ Version: 6.6.42 ≤ Version: 6.9.11 ≤ |
||
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/bluetooth/hci_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
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"status": "affected",
"version": "0d151a103775dd9645c78c97f77d6e2a5298d913",
"versionType": "git"
},
{
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"status": "affected",
"version": "0d151a103775dd9645c78c97f77d6e2a5298d913",
"versionType": "git"
},
{
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"status": "affected",
"version": "0d151a103775dd9645c78c97f77d6e2a5298d913",
"versionType": "git"
},
{
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"status": "affected",
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"versionType": "git"
},
{
"status": "affected",
"version": "48542881997e17b49dc16b93fe910e0cfcf7a9f9",
"versionType": "git"
},
{
"status": "affected",
"version": "9cfc84b1d464cc024286f42a090718f9067b80ed",
"versionType": "git"
},
{
"status": "affected",
"version": "ddeda6ca5f218b668b560d90fc31ae469adbfd92",
"versionType": "git"
},
{
"status": "affected",
"version": "d2ce562a5aff1dcd0c50d9808ea825ef90da909f",
"versionType": "git"
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{
"status": "affected",
"version": "96600c2e5ee8213dbab5df1617293d8e847bb4fa",
"versionType": "git"
},
{
"status": "affected",
"version": "d6cbce18370641a21dd889e8613d8153df15eb39",
"versionType": "git"
},
{
"status": "affected",
"version": "3f939bd73fed12dddc2a32a76116c19ca47c7678",
"versionType": "git"
},
{
"lessThan": "4.20",
"status": "affected",
"version": "4.19.319",
"versionType": "semver"
},
{
"lessThan": "5.5",
"status": "affected",
"version": "5.4.281",
"versionType": "semver"
},
{
"lessThan": "5.11",
"status": "affected",
"version": "5.10.223",
"versionType": "semver"
},
{
"lessThan": "5.16",
"status": "affected",
"version": "5.15.164",
"versionType": "semver"
},
{
"lessThan": "6.2",
"status": "affected",
"version": "6.1.101",
"versionType": "semver"
},
{
"lessThan": "6.7",
"status": "affected",
"version": "6.6.42",
"versionType": "semver"
},
{
"lessThan": "6.10",
"status": "affected",
"version": "6.9.11",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"net/bluetooth/hci_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.10"
},
{
"lessThan": "6.10",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.97",
"versionStartIncluding": "6.10",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.40",
"versionStartIncluding": "6.10",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.5",
"versionStartIncluding": "6.10",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "6.10",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "4.19.319",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.4.281",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.10.223",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.15.164",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.1.101",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.6.42",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.9.11",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: Fix UAF in hci_unregister_dev()\n\nhci_unregister_dev() does not disable cmd_timer and ncmd_timer\nbefore the hci_dev structure is freed. If a timeout fires\nduring device teardown, the callback dereferences freed memory\n(including the hdev-\u003ereset function pointer), leading to a\nuse-after-free.\n\nAdd disable_delayed_work_sync() calls alongside the existing\ndisable_work_sync() calls to ensure both timers are fully\nquiesced before teardown proceeds."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The UAF is reached only during hci_unregister_dev() teardown (e.g. closing /dev/vhci, USB/btusb disconnect, hci_ldisc detach, or driver removal); adjacent Bluetooth peers can arm cmd_timer/ncmd_timer via HCI timeouts but cannot invoke unregister, so exploitation requires local device/syscall access.\nAC:L - An attacker controls both sides of the race\u2014arming cmd_timer (2s) or ncmd_timer (4s) by withholding HCI command completions while closing /dev/vhci to run hci_unregister_dev(), and disable_work_sync(cmd_work) can queue cmd_timer immediately before teardown; the cycle is repeatable.\nPR:L - vhci_open() has no capable() check, so any principal granted /dev/vhci (syzkaller, containers, Android bluetooth uid, permissive udev) can create/destroy virtual HCI controllers and inject frames without init-namespace root, matching prior hci_unregister_dev teardown UAF scores.\nUI:N - The attacker performs device creation, HCI traffic injection, and teardown from its own process via open/write/close on /dev/vhci or equivalent local transport; no victim interaction or cooperation is required beyond existing device-node access.\nS:U - Corruption is confined to kernel slab memory and workqueue/timer state within the same kernel security authority; exploitation yields standard kernel privilege escalation, not VM escape, IOMMU bypass, or cross-sandbox boundary crossing.\nC:H - hci_cmd_timeout() and hci_ncmd_timeout() dereference the freed hci_dev (req_skb, flags, workqueue, name) after kfree(); UAF on the hci_dev slab enables controlled reallocation and arbitrary kernel memory read/pointer disclosure via heap spraying.\nI:H - hci_cmd_timeout() invokes the freed hdev-\u003ereset function pointer and re-queues cmd_work on hdev-\u003eworkqueue; attacker-controlled contents in the reclaimed hci_dev object provide arbitrary write and control-flow hijack primitives per kernel UAF scoring guidance.\nA:H - Timer callbacks operating on freed hci_dev memory cause KASAN slab-use-after-free reports, kernel oops/panic, and can queue work onto destroyed workqueues; even failed exploitation reliably crashes or hangs the affected controller path."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T05:45:38.299Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/48c7ad6afcc58c2cda11fed39791708103b6a644"
},
{
"url": "https://git.kernel.org/stable/c/a0fd1086a57b982f8c24ae4ab165c2af39fe1735"
},
{
"url": "https://git.kernel.org/stable/c/672d52d9412252e61b8de8d773ccdf5a277cf540"
},
{
"url": "https://git.kernel.org/stable/c/5edcc018fa6e80b2c478454a4a8229c23d67c181"
}
],
"title": "Bluetooth: hci_core: Fix UAF in hci_unregister_dev()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-74302",
"datePublished": "2026-08-15T05:58:04.638Z",
"dateReserved": "2026-08-15T05:44:03.882Z",
"dateUpdated": "2026-08-17T05:45:38.299Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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