FKIE_CVE-2026-64380
Vulnerability from fkie_nvd - Published: 2026-07-25 10:17 - Updated: 2026-09-08 14:06
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved:
smb: client: harden POSIX SID length parsing
posix_info_sid_size() reads sid[1] to obtain the subauthority count,
but its existing boundary check still accepts buffers with only one
remaining byte. Require two bytes before reading sid[1] so all client
paths that reuse the helper reject truncated POSIX SIDs safely.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | 7.2 |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"fs/smb/client/smb2pdu.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "171605aed68380c2fa75dff9b3a1ed427c50065b",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "4213c1208978483021d7d125c131de3985d38f61",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "96e889bc1e759c83f25093e8c2f3da31b4973f30",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "0de5b8e76847f5de26f364a82c6602c4881c30da",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "427eb7eb46425fec845a43e861f3d6e2899cae59",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "86c5d470f5d42e61123b2f4b4f0b91f4eee5b980",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "46a84715a015cb48e1b9c219dc88c03d8a541ea4",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
},
{
"lessThan": "7ad2bcf2441430bb2e918fb3ef9a90d775a6e422",
"status": "affected",
"version": "349e13ad30b45998bb9937cfe0b32be6f951976d",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"fs/smb/client/smb2pdu.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.7"
},
{
"lessThan": "5.7",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.96",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.4",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "F5BDA79D-4919-45F0-A4BC-DD6AAE3844CB",
"versionEndExcluding": "5.10.261",
"versionStartIncluding": "5.7",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "8E99FB01-CD93-41AF-A653-3F450652B9A6",
"versionEndExcluding": "5.15.212",
"versionStartIncluding": "5.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "092233C7-F4E0-40C8-BD4D-A28FE50DFE20",
"versionEndExcluding": "6.1.178",
"versionStartIncluding": "5.16",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE",
"versionEndExcluding": "6.6.145",
"versionStartIncluding": "6.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2",
"versionEndExcluding": "6.12.96",
"versionStartIncluding": "6.7",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7",
"versionEndExcluding": "6.18.39",
"versionStartIncluding": "6.13",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42",
"versionEndExcluding": "7.1.4",
"versionStartIncluding": "6.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*",
"matchCriteriaId": "5E8B9085-7ADB-4A05-89EF-12949B6A0509",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: harden POSIX SID length parsing\n\nposix_info_sid_size() reads sid[1] to obtain the subauthority count,\nbut its existing boundary check still accepts buffers with only one\nremaining byte. Require two bytes before reading sid[1] so all client\npaths that reuse the helper reject truncated POSIX SIDs safely."
}
],
"id": "CVE-2026-64380",
"lastModified": "2026-09-08T14:06:05.950",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 8.2,
"baseSeverity": "HIGH",
"confidentialityImpact": "LOW",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 4.2,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
}
]
},
"published": "2026-07-25T10:17:21.220",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/0de5b8e76847f5de26f364a82c6602c4881c30da"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/171605aed68380c2fa75dff9b3a1ed427c50065b"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/4213c1208978483021d7d125c131de3985d38f61"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/427eb7eb46425fec845a43e861f3d6e2899cae59"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/46a84715a015cb48e1b9c219dc88c03d8a541ea4"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/7ad2bcf2441430bb2e918fb3ef9a90d775a6e422"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/86c5d470f5d42e61123b2f4b4f0b91f4eee5b980"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/96e889bc1e759c83f25093e8c2f3da31b4973f30"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
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.
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.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…