CVE-2026-74534
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix refcounting of iso_conn iso_conn_del() and iso_chan_del() have a race that results to double-put of iso_conn: [Task hdev->workqueue] [Task 2] iso_conn_del iso_chan_del iso_conn_hold_unless_zero iso_conn_lock iso_conn_lock conn->sk = NULL iso_conn_unlock sk = iso_sock_hold(conn) <---------´ if (!sk) iso_conn_put iso_conn_put iso_conn_put /* UAF */ The extra put for !sk in iso_conn_del() is currently required since failing iso_chan_add() may leave iso_conn not associated with any sk. Fix by having iso_pi(sk)->conn own refcount when non-NULL, so iso_conn_del does not need to put it. Adjust the iso_conn_add() refcounting so that conn is put if it does not get associated with an sk.
Severity
HIGH
CVSS score
8.8
(v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 13:17:58.700000
Last modified
2026-10-23 09:17:07.510000
View original CVE JSON
{
"id": "CVE-2026-74534",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-08-15T13:17:58.700",
"lastModified": "2026-10-23T09:17:07.510",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: fix refcounting of iso_conn\n\niso_conn_del() and iso_chan_del() have a race that results to double-put\nof iso_conn:\n\n [Task hdev->workqueue] [Task 2]\n iso_conn_del iso_chan_del\n iso_conn_hold_unless_zero iso_conn_lock\n iso_conn_lock conn->sk = NULL\n iso_conn_unlock\n sk = iso_sock_hold(conn) <---------´\n if (!sk) iso_conn_put iso_conn_put\n iso_conn_put /* UAF */\n\nThe extra put for !sk in iso_conn_del() is currently required since\nfailing iso_chan_add() may leave iso_conn not associated with any sk.\n\nFix by having iso_pi(sk)->conn own refcount when non-NULL, so\niso_conn_del does not need to put it. Adjust the iso_conn_add()\nrefcounting so that conn is put if it does not get associated with an\nsk."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/bluetooth/iso.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "a58d0f5dac322e16cc75334d000666512341bde5",
"lessThan": "42c8bd6ac81e21200bb90f1eaf43d19352eec6d7",
"versionType": "git",
"status": "affected"
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{
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{
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{
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{
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"defaultStatus": "affected",
"programFiles": [
"net/bluetooth/iso.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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{
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"status": "affected"
},
{
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"versionType": "semver",
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},
{
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"versionType": "semver",
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},
{
"version": "6.18.44",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1.8",
"lessThanOrEqual": "7.1.*",
"versionType": "semver",
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},
{
"version": "7.2",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"attackVector": "ADJACENT_NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.8,
"impactScore": 5.9
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-16T18:59:26.294931Z",
"id": "CVE-2026-74534",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
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{
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],
"role": "CISA Coordinator",
"version": "2.0.3"
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"references": [
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"url": "https://git.kernel.org/stable/c/3b921533e8aa95b77aadcf31737595578e735f3c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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}