CVE-2026-31470
In the Linux kernel, the following vulnerability has been resolved:
virt: tdx-guest: Fix handling of host controlled 'quote' buffer length
Validate host controlled value `quote_buf->out_len` that determines how many bytes of the quote are copied out to guest userspace. In TDX environments with remote attestation, quotes are not considered private, and can be forwarded to an attestation server.
Catch scenarios where the host specifies a response length larger than the guest's allocation, or otherwise races modifying the response while the guest consumes it.
This prevents contents beyond the pages allocated for `quote_buf` (up to TSM_REPORT_OUTBLOB_MAX) from being read out to guest userspace, and possibly forwarded in attestation requests.
Leer descripción completaMostrar menos
Recall that some deployments want per-container configs-tsm-report interfaces, so the leak may cross container protection boundaries, not just local root.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- Puntuación base: 7.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.17%
- Percentil entre todas las CVEs puntuadas: 5
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation85 % - Impacto principal
T1005Data from Local Systemcollection80 %
Acceso local (AV:L) con privilegios (PR:L) permite leer memoria más allá de los límites asignados (CWE-787, buffer over-read) en el kernel de Linux, extrayendo datos sensibles como quotes de atestación.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-787
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-31470",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.1,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "f4738f56d1dc62aaba69b33702a5ab098f1b8c63",
"lessThan": "a079a62883e3365de592cea9f7a669d8115433b0",
"versionType": "git"
},
{
"status": "affected",
"version": "f4738f56d1dc62aaba69b33702a5ab098f1b8c63",
"lessThan": "6f3c8795ae9ba74fa10fe979293d1904712d3fb1",
"versionType": "git"
},
{
"status": "affected",
"version": "f4738f56d1dc62aaba69b33702a5ab098f1b8c63",
"lessThan": "02ca2d9d197723696cb9cc0cb159eb7e8bf5f89b",
"versionType": "git"
},
{
"status": "affected",
"version": "f4738f56d1dc62aaba69b33702a5ab098f1b8c63",
"lessThan": "c3fd16c3b98ed726294feab2f94f876290bf7b61",
"versionType": "git"
}
],
"programFiles": [
"drivers/virt/coco/tdx-guest/tdx-guest.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.7"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.7",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.80",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.21",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.11",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/virt/coco/tdx-guest/tdx-guest.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-04-22T14:16:43.473",
"references": [
{
"url": "https://git.kernel.org/stable/c/02ca2d9d197723696cb9cc0cb159eb7e8bf5f89b",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6f3c8795ae9ba74fa10fe979293d1904712d3fb1",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a079a62883e3365de592cea9f7a669d8115433b0",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/c3fd16c3b98ed726294feab2f94f876290bf7b61",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-787"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirt: tdx-guest: Fix handling of host controlled 'quote' buffer length\n\nValidate host controlled value `quote_buf->out_len` that determines how\nmany bytes of the quote are copied out to guest userspace. In TDX\nenvironments with remote attestation, quotes are not considered private,\nand can be forwarded to an attestation server.\n\nCatch scenarios where the host specifies a response length larger than\nthe guest's allocation, or otherwise races modifying the response while\nthe guest consumes it.\n\nThis prevents contents beyond the pages allocated for `quote_buf`\n(up to TSM_REPORT_OUTBLOB_MAX) from being read out to guest userspace,\nand possibly forwarded in attestation requests.\n\nRecall that some deployments want per-container configs-tsm-report\ninterfaces, so the leak may cross container protection boundaries, not\njust local root."
}
],
"lastModified": "2026-06-17T10:33:48.230",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "97EB19EC-A11E-49C6-9D2F-6F6EC6CB98B6",
"versionEndExcluding": "6.12.80",
"versionStartIncluding": "6.7"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "ED39847A-3B46-4729-B7CA-B2C30B9FA8FE",
"versionEndExcluding": "6.18.21",
"versionStartIncluding": "6.13"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "4CA2E747-A9EC-4518-9AA2-B4247FC748B7",
"versionEndExcluding": "6.19.11",
"versionStartIncluding": "6.19"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}