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vuln-cve/data/2026/68xxx/CVE-2026-68202.json
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{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-68202",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2026-07-30T09:28:09.374Z",
"datePublished": "2026-08-10T12:00:21.279Z",
"dateUpdated": "2026-10-19T20:58:57.086Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-08-23T12:46:08.116Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: seq: close a re-opened queue timer in the destructor\n\nqueue_delete() closes the queue timer, then frees it. snd_seq_timer_close()\nclears q->timer->timeri. snd_use_lock_sync() then drains borrowers, and\nsnd_seq_timer_delete() frees q->timer.\n\nA borrower can re-open the timer inside that window. A SET_QUEUE_CLIENT\nthat took a queueptr() use_lock reference before the queue was unlinked\nruns snd_seq_timer_open() after the close. Open refuses re-open only while\ntimeri is set, and the close just cleared it, so it re-opens timeri.\n\nsnd_seq_timer_delete() does not close that instance. Its snd_seq_timer_stop()\nis a no-op, because running was cleared first. So it frees q->timer with the\ninstance still live. The queue is freed next.\n\nThe instance stays on the global timer with callback_data pointing at the\nfreed queue. A non-owner START on the unlocked queue arms it. The next tick\nderefs the freed queue in snd_seq_timer_interrupt().\n\nReachable by an unprivileged user with access to /dev/snd/seq. No CAP and\nno queue ownership required.\n\nClose any lingering instance in the destructor. There, ->timeri can no\nlonger change: the queue is unlinked and all use_lock borrowers have\ndrained, so no snd_seq_queue_use() can re-open it. Close it before clearing\nq->timer. snd_timer_close() waits for any in-flight snd_seq_timer_interrupt()\nto finish, and that callback still reads q->timer (via snd_seq_check_queue()),\nso q->timer must stay valid until it drains."
}
],
"metrics": [
{
"cvssV3_1": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 7.8,
"baseSeverity": "HIGH"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The bug is reached through ioctls on the local character device /dev/snd/seq (SNDRV_SEQ_IOCTL_CREATE_QUEUE/DELETE_QUEUE/SET_QUEUE_CLIENT); no network or adjacent-network path exists to the ALSA sequencer.\nAC:L - The attacker controls both sides of the race — one thread deletes the queue while another spins on SET_QUEUE_CLIENT holding a queueptr() reference — and can retry the loop indefinitely on a default kernel with CONFIG_SND_SEQUENCER, so the window is reliably hit.\nPR:L - Only an unprivileged local user able to open /dev/snd/seq is needed; snd_seq_queue_use() performs no owner or access check and no capability is required, as the fix commit states explicitly.\nUI:N - The attacker's own threads create, delete and re-use the queue and the global system timer fires on its own; no victim action is involved.\nS:U - The use-after-free corrupts kernel heap objects within the same kernel security authority, giving at most kernel privilege escalation rather than crossing a VM, IOMMU or sandbox boundary.\nC:H - The stale timer instance dereferences the freed snd_seq_queue and snd_seq_timer, reading tick/time fields and freed prioq pointers that can be reclaimed by attacker-sprayed objects, giving a route to disclose arbitrary kernel memory.\nI:H - snd_seq_timer_interrupt() writes cur_time, tick and last_update into the freed snd_seq_timer slab and snd_seq_check_queue() dispatches events through freed queue pointers, yielding a controllable write primitive on reclaimed heap memory suitable for privilege escalation.\nA:H - Even unexploited, the timer callback derefs freed memory and takes a spinlock in a freed object from interrupt context, causing oops, lock corruption or panic — a repeatable denial of service for any local user."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"sound/core/seq/seq_timer.c"
],
"versions": [
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "b7feeaca1f53b10df9b4de9eaf611767ca70dc92",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "7478ef94b49bc9789cf1a003deec58b42283dde4",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "9d9be6fc30f384f92c4e1b8ed40bd9d4796b7833",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "fb40d03ed792a8a8bf77aa0ee15df57b0ff78b07",
"status": "affected",
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},
{
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"lessThan": "24f0cabf173539f048946c8fc221131dc221f277",
"status": "affected",
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},
{
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"lessThan": "6a10025c7fd09a7d2af37a3ae1da188569fce470",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "31a6163e301d832060f8236f1ed17cbc1ca198df",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "2c4dc0ed50b05cd847a4b34b8cebf0775f19aeb9",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"sound/core/seq/seq_timer.c"
],
"versions": [
{
"version": "2.6.12",
"status": "affected"
},
{
"version": "0",
"lessThan": "2.6.12",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.10.266",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.15.217",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.1.183",
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.6.148",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.12.101",
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.18.42",
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.1.6",
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "2.6.12",
"versionEndExcluding": "5.10.266"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "2.6.12",
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},
{
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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},
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "2.6.12",
"versionEndExcluding": "6.12.101"
},
{
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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],
"references": [
{
"url": "https://git.kernel.org/stable/c/b7feeaca1f53b10df9b4de9eaf611767ca70dc92"
},
{
"url": "https://git.kernel.org/stable/c/7478ef94b49bc9789cf1a003deec58b42283dde4"
},
{
"url": "https://git.kernel.org/stable/c/9d9be6fc30f384f92c4e1b8ed40bd9d4796b7833"
},
{
"url": "https://git.kernel.org/stable/c/fb40d03ed792a8a8bf77aa0ee15df57b0ff78b07"
},
{
"url": "https://git.kernel.org/stable/c/24f0cabf173539f048946c8fc221131dc221f277"
},
{
"url": "https://git.kernel.org/stable/c/6a10025c7fd09a7d2af37a3ae1da188569fce470"
},
{
"url": "https://git.kernel.org/stable/c/31a6163e301d832060f8236f1ed17cbc1ca198df"
},
{
"url": "https://git.kernel.org/stable/c/2c4dc0ed50b05cd847a4b34b8cebf0775f19aeb9"
}
],
"title": "ALSA: seq: close a re-opened queue timer in the destructor",
"x_generator": {
"engine": "bippy-1.2.0"
}
},
"adp": [
{
"metrics": [
{
"other": {
"type": "ssvc",
"content": {
"id": "CVE-2026-68202",
"role": "CISA Coordinator",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-10-16T15:45:51.106270Z"
}
}
}
],
"problemTypes": [
{
"descriptions": [
{
"lang": "en",
"type": "CWE",
"cweId": "CWE-416",
"description": "CWE-416 Use After Free"
}
]
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP",
"dateUpdated": "2026-10-19T20:58:57.086Z"
}
}
]
}
}