CVE-2026-64379

Estado: AnalizadaAlta (7.1)—

In the Linux kernel, the following vulnerability has been resolved:

smb: client: mask server-provided mode to 07777 in modefromsid

When modefromsid is active, parse_dacl() applies the server-provided sub_auth[2] value from the NFS mode SID to cf_mode without masking to 07777. Apply the correct masking, same as in the read path.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Puntuación base: 7.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.31%
Percentil entre todas las CVEs puntuadas: 22
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.

ExplotaciónT1203 Exploitation for Client Executionexecution85 %
Impacto principalT1565.001 Stored Data Manipulationimpact75 %
Impacto secundarioT1499.004 Application or System Exploitationimpact60 %

Vector CVSS con UI:R indica explotación en cliente (T1203). La falta de enmascaramiento de permisos permite modificación de atributos de archivo (I:L) y potencial denegación de servicio (A:H) en kernel Linux.

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

Restrict File and Directory Permissions Remote Data Storage Filter Network Traffic Encrypt Sensitive Information Application Isolation and Sandboxing Exploit Protection

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-64379",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.1,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H",
          "integrityImpact": "LOW",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 4.2,
        "exploitabilityScore": 2.8
      }
    ]
  },
  "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": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "5f6f2241034f189c69d4d0b5f8fe24a0c25b0c14",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "ee2216dbdf0c677e89bb43e03247dba590ed00ef",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "f511807feee7cb29b61bdfa86472c7e9e2e5df94",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "08c600b7e1818539ba5efee4cdb06215c245ca78",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "b84e002e0df26bbc6cbd3ca01b8212601fe0ae7d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "c6c484a7d5bff6b929a86d7ed5130f29834c6a0d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "f80add1bfb3425100a325b14f19648e75669a954",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e2f8fbfb8d09c06decde162090fac3ee220aa280",
              "lessThan": "e3d9c7160d483fc8f9e225aafad8ecbbc43f3151",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/smb/client/cifsacl.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.4"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.4",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.96",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.39",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/smb/client/cifsacl.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-07-25T10:17:21.090",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/08c600b7e1818539ba5efee4cdb06215c245ca78",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5f6f2241034f189c69d4d0b5f8fe24a0c25b0c14",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b84e002e0df26bbc6cbd3ca01b8212601fe0ae7d",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c6c484a7d5bff6b929a86d7ed5130f29834c6a0d",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e3d9c7160d483fc8f9e225aafad8ecbbc43f3151",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ee2216dbdf0c677e89bb43e03247dba590ed00ef",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f511807feee7cb29b61bdfa86472c7e9e2e5df94",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f80add1bfb3425100a325b14f19648e75669a954",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: mask server-provided mode to 07777 in modefromsid\n\nWhen modefromsid is active, parse_dacl() applies the server-provided\nsub_auth[2] value from the NFS mode SID to cf_mode without masking to\n07777. Apply the correct masking, same as in the read path."
    }
  ],
  "lastModified": "2026-09-08T14:08:51.350",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "DE25B17F-9753-425C-B1AE-65F29C8B2ACE",
              "versionEndExcluding": "5.10.261",
              "versionStartIncluding": "5.4"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "8E99FB01-CD93-41AF-A653-3F450652B9A6",
              "versionEndExcluding": "5.15.212",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "092233C7-F4E0-40C8-BD4D-A28FE50DFE20",
              "versionEndExcluding": "6.1.178",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE",
              "versionEndExcluding": "6.6.145",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2",
              "versionEndExcluding": "6.12.96",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7",
              "versionEndExcluding": "6.18.39",
              "versionStartIncluding": "6.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42",
              "versionEndExcluding": "7.1.4",
              "versionStartIncluding": "6.19"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "5E8B9085-7ADB-4A05-89EF-12949B6A0509"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1FC0D50D-9D58-4947-A197-A5A3FF07E7E3"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}