FKIE_CVE-2026-22995
Vulnerability from fkie_nvd - Published: 2026-01-23 16:15 - Updated: 2026-06-17 10:20
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved:
ublk: fix use-after-free in ublk_partition_scan_work
A race condition exists between the async partition scan work and device
teardown that can lead to a use-after-free of ub->ub_disk:
1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk()
2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does:
- del_gendisk(ub->ub_disk)
- ublk_detach_disk() sets ub->ub_disk = NULL
- put_disk() which may free the disk
3. The worker ublk_partition_scan_work() then dereferences ub->ub_disk
leading to UAF
Fix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold
a reference to the disk during the partition scan. The spinlock in
ublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker
either gets a valid reference or sees NULL and exits early.
Also change flush_work() to cancel_work_sync() to avoid running the
partition scan work unnecessarily when the disk is already detached.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | * | |
| linux | linux_kernel | 6.19 |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/block/ublk_drv.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "72e28774e9644c2bdbb4920842fbf77103a15a85",
"status": "affected",
"version": "63dfbcd59b4b823eac4441efff10b1c303c8f49f",
"versionType": "git"
},
{
"lessThan": "f0d385f6689f37a2828c686fb279121df006b4cb",
"status": "affected",
"version": "7fc4da6a304bdcd3de14fc946dc2c19437a9cc5a",
"versionType": "git"
}
]
},
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/block/ublk_drv.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "6.18.6",
"status": "affected",
"version": "6.18.4",
"versionType": "semver"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "27849DC4-2BBE-4536-8F33-2616A53ACA55",
"versionEndExcluding": "6.18.6",
"versionStartIncluding": "6.18.4",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*",
"matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB",
"vulnerable": true
}
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"negate": false,
"operator": "OR"
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],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nublk: fix use-after-free in ublk_partition_scan_work\n\nA race condition exists between the async partition scan work and device\nteardown that can lead to a use-after-free of ub-\u003eub_disk:\n\n1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk()\n2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does:\n - del_gendisk(ub-\u003eub_disk)\n - ublk_detach_disk() sets ub-\u003eub_disk = NULL\n - put_disk() which may free the disk\n3. The worker ublk_partition_scan_work() then dereferences ub-\u003eub_disk\n leading to UAF\n\nFix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold\na reference to the disk during the partition scan. The spinlock in\nublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker\neither gets a valid reference or sees NULL and exits early.\n\nAlso change flush_work() to cancel_work_sync() to avoid running the\npartition scan work unnecessarily when the disk is already detached."
},
{
"lang": "es",
"value": "Se ha resuelto la siguiente vulnerabilidad en el kernel de Linux:\n\nublk: corrige uso despu\u00e9s de liberaci\u00f3n en ublk_partition_scan_work\n\nExiste una condici\u00f3n de carrera entre el trabajo de escaneo de particiones as\u00edncrono y el desmontaje del dispositivo que puede llevar a un uso despu\u00e9s de liberaci\u00f3n de ub-\u0026gt;ub_disk:\n\n1. ublk_ctrl_start_dev() programa partition_scan_work despu\u00e9s de add_disk()\n2. ublk_stop_dev() llama a ublk_stop_dev_unlocked() que hace:\n - del_gendisk(ub-\u0026gt;ub_disk)\n - ublk_detach_disk() establece ub-\u0026gt;ub_disk = NULL\n - put_disk() que puede liberar el disco\n3. El worker ublk_partition_scan_work() entonces desreferencia ub-\u0026gt;ub_disk llevando a UAF\n\nCorrige esto usando ublk_get_disk()/ublk_put_disk() en el worker para mantener una referencia al disco durante el escaneo de particiones. El spinlock en ublk_get_disk() se sincroniza con ublk_detach_disk() asegurando que el worker o bien obtiene una referencia v\u00e1lida o ve NULL y sale temprano.\n\nTambi\u00e9n cambia flush_work() a cancel_work_sync() para evitar ejecutar innecesariamente el trabajo de escaneo de particiones cuando el disco ya est\u00e1 desmontado."
}
],
"id": "CVE-2026-22995",
"lastModified": "2026-06-17T10:20:40.373",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"published": "2026-01-23T16:15:55.603",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/72e28774e9644c2bdbb4920842fbf77103a15a85"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/f0d385f6689f37a2828c686fb279121df006b4cb"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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