FKIE_CVE-2026-64308

Vulnerability from fkie_nvd - Published: 2026-07-25 10:17 - Updated: 2026-11-06 17:18
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD) Sashiko notes: > if SEV initialization fails and KVM is actively running normal VMs, could a > userspace process trigger this code path via /dev/sev ioctls (e.g., > SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN > execution for an active VM trigger a general protection fault and crash the > host? The SEV firmware docs for SNP_VLEK_LOAD note: > On SNP_SHUTDOWN, the VLEK is deleted. That is, the initialization/shutdown wrapper here is pointless, because the firmware immediately throws away the key anyway. Instead, refuse to do anything if SNP has not been previously initialized. This is an ABI break: before, this was a no-op and almost certainly a mistake by userspace, and now it returns -ENODEV. ABI compatibility could be maintained here by simply returning 0 in the check instead.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/61cf5eef20657bff9ca235fe938a99ce5ff65c06Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8836801847b9479ac046cb18a24981e1b0b05e9dPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/92567ed9306d5a3d1b007eb4faeff30cc3ffc3e4Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f91e9dbb5845d1e5abf1028e6df57dcf61583e1bPatch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/crypto/ccp/sev-dev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "61cf5eef20657bff9ca235fe938a99ce5ff65c06",
              "status": "affected",
              "version": "1c3506ea8599a3ad1b9aae5cbd573134f8d18db7",
              "versionType": "git"
            },
            {
              "lessThan": "92567ed9306d5a3d1b007eb4faeff30cc3ffc3e4",
              "status": "affected",
              "version": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c",
              "versionType": "git"
            },
            {
              "lessThan": "8836801847b9479ac046cb18a24981e1b0b05e9d",
              "status": "affected",
              "version": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c",
              "versionType": "git"
            },
            {
              "lessThan": "f91e9dbb5845d1e5abf1028e6df57dcf61583e1b",
              "status": "affected",
              "version": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c",
              "versionType": "git"
            },
            {
              "lessThan": "6.12.96",
              "status": "affected",
              "version": "6.12.75",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/crypto/ccp/sev-dev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "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": "0C1E3642-D5B1-428A-9CC8-2B6059DEA06A",
              "versionEndExcluding": "6.12.96",
              "versionStartIncluding": "6.12.75",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "FFBD7467-7FB0-4538-9CC0-98199E9EC402",
              "versionEndExcluding": "6.18.39",
              "versionStartIncluding": "6.16",
              "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
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD)\n\nSashiko notes:\n\n\u003e if SEV initialization fails and KVM is actively running normal VMs, could a\n\u003e userspace process trigger this code path via /dev/sev ioctls (e.g.,\n\u003e SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n\u003e execution for an active VM trigger a general protection fault and crash the\n\u003e host?\n\nThe SEV firmware docs for SNP_VLEK_LOAD note:\n\n\u003e On SNP_SHUTDOWN, the VLEK is deleted.\n\nThat is, the initialization/shutdown wrapper here is pointless, because the\nfirmware immediately throws away the key anyway. Instead, refuse to do\nanything if SNP has not been previously initialized.\n\nThis is an ABI break: before, this was a no-op and almost certainly a\nmistake by userspace, and now it returns -ENODEV. ABI compatibility could be\nmaintained here by simply returning 0 in the check instead."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ncrypto: ccp - No inicializar SNP para ioctl(SNP_VLEK_LOAD)\n\nSashiko se\u00f1ala:\n\n\u003e si la inicializaci\u00f3n de SEV falla y KVM est\u00e1 ejecutando activamente m\u00e1quinas virtuales normales, \u00bfpodr\u00eda un\n\u003e proceso de espacio de usuario activar esta ruta de c\u00f3digo a trav\u00e9s de ioctls de /dev/sev (por ejemplo,\n\u003e SEV_PDH_GEN) y poner a cero MSR_VM_HSAVE_PA globalmente? \u00bfLa siguiente ejecuci\u00f3n de VMRUN\n\u003e para una m\u00e1quina virtual activa activar\u00eda una falla de protecci\u00f3n general y bloquear\u00eda el\n\u003e anfitri\u00f3n?\n\nLa documentaci\u00f3n del firmware de SEV para SNP_VLEK_LOAD se\u00f1ala:\n\n\u003e En SNP_SHUTDOWN, el VLEK es eliminado.\n\nEs decir, el envoltorio de inicializaci\u00f3n/apagado aqu\u00ed es in\u00fatil, porque el\nfirmware desecha inmediatamente la clave de todos modos. En su lugar, negarse a hacer\nnada si SNP no ha sido inicializado previamente.\n\nEsto es una ruptura de ABI: antes, esto era una operaci\u00f3n nula y casi con certeza un\nerror del espacio de usuario, y ahora devuelve -ENODEV. La compatibilidad ABI podr\u00eda ser\nmantenida aqu\u00ed simplemente devolviendo 0 en la verificaci\u00f3n en su lugar."
    }
  ],
  "id": "CVE-2026-64308",
  "lastModified": "2026-11-06T17:18:47.027",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-64308",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-11-06T16:34:39.644370Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-25T10:17:11.917",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/61cf5eef20657bff9ca235fe938a99ce5ff65c06"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/8836801847b9479ac046cb18a24981e1b0b05e9d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/92567ed9306d5a3d1b007eb4faeff30cc3ffc3e4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/f91e9dbb5845d1e5abf1028e6df57dcf61583e1b"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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