CVE-2026-89450
In the Linux kernel, the following vulnerability has been resolved:
iommu/tegra241-cmdqv: Reject a vSID wider than the SID_MATCH field
tegra241_vintf_init_vsid() programs the guest-provided vSID into SID_MATCH, whose VIRT_SID field spans bits [20:1] with bit 0 as the match-enable flag. The HW therefore matches only a 20-bit Stream ID.
The bound check rejects only virt_sid > UINT_MAX, which admits a value far wider than the field. The write "virt_sid << 1 | 0x1" then drops every bit above 20: a virt_sid of 0x80000000 lands as SID_MATCH = 0x1, a valid match on vSID 0, so the entry aliases the wrong Stream ID. Because vdev->virt_id is guest-controlled, a VMM can trigger it.
Leer descripción completaMostrar menos
Validate virt_sid against the field width with FIELD_MAX(), and program the register with FIELD_PREP() so the value and the field stay consistent.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.17%
- Percentil entre todas las CVEs puntuadas: 6
- 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
T1078.002Domain Accountsstealth · persistence · privilege escalation · initial access75 % - Impacto secundario
T1550.001Application Access Tokenlateral movement70 %
Acceso local (AV:L, PR:L) sin interacción del usuario permite escalada de privilegios al manipular vSID en IOMMU; VMM puede suplantar identidades de Stream ID para eludir controles de acceso.
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)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
JSON original (NVD)
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{
"id": "CVE-2026-89450",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 8.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 6,
"exploitabilityScore": 2
}
]
},
"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": "4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7",
"lessThan": "d903d99ffd22b0180bd745a43f221c21bcdd8d7c",
"versionType": "git"
},
{
"status": "affected",
"version": "4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7",
"lessThan": "445204550f894ca325ac80a21e3df177ad073798",
"versionType": "git"
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{
"status": "affected",
"version": "4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7",
"lessThan": "4379610c79bd88ddbea10e7f6c21e16d4b338c6b",
"versionType": "git"
}
],
"programFiles": [
"drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-11T20:19:25.603",
"references": [
{
"url": "https://git.kernel.org/stable/c/4379610c79bd88ddbea10e7f6c21e16d4b338c6b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/445204550f894ca325ac80a21e3df177ad073798",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/d903d99ffd22b0180bd745a43f221c21bcdd8d7c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/tegra241-cmdqv: Reject a vSID wider than the SID_MATCH field\n\ntegra241_vintf_init_vsid() programs the guest-provided vSID into SID_MATCH,\nwhose VIRT_SID field spans bits [20:1] with bit 0 as the match-enable flag.\nThe HW therefore matches only a 20-bit Stream ID.\n\nThe bound check rejects only virt_sid > UINT_MAX, which admits a value far\nwider than the field. The write \"virt_sid << 1 | 0x1\" then drops every bit\nabove 20: a virt_sid of 0x80000000 lands as SID_MATCH = 0x1, a valid match\non vSID 0, so the entry aliases the wrong Stream ID. Because vdev->virt_id\nis guest-controlled, a VMM can trigger it.\n\nValidate virt_sid against the field width with FIELD_MAX(), and program the\nregister with FIELD_PREP() so the value and the field stay consistent."
}
],
"lastModified": "2026-09-13T07:17:09.350",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}