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CVE-2026-89450

Estado: RecibidaAlta (8.8)—

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

Probabilidad de explotación (EPSS)

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.

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"
            },
            {
              "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"
}