CVE-2026-64381

Estado: AnalizadaAlta (7.8)—

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

smb: client: Fix next buffer leak in receive_encrypted_standard()

receive_encrypted_standard() allocates next_buffer before checking whether the number of compound PDUs already reached MAX_COMPOUND. If the limit check fails, the function returns immediately and the newly allocated next_buffer is not assigned to server->smallbuf/server->bigbuf, making it leaked.

Move the MAX_COMPOUND check before allocating next_buffer.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.13%
Percentil entre todas las CVEs puntuadas: 2
Fecha de la puntuación: 6/10/2026

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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Impacto principalT1059 Command and Scripting Interpreterexecution75 %

AV:L/PR:L sin UI indica escalada de privilegios local. Leak de memoria en kernel (CWE-787 buffer overflow) con C:H/I:H/A:H sugiere ejecución de código con permisos elevados desde contexto local con privilegios.

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-787

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-64381",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.8,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "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": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "94e4f672db029414b9888b5137a7559f1febf2d8",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "68fc0b6cc03ca58060c0f36454e169f5fe258974",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "07e0ab81df1790afa35732a4e8e07ff831b29008",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "9136a08dc29328edd9867f2545e73906ac9df93b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "67097772df7791c53d608f04bd31c676ccf79b83",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "297243e365fc9fe2f8e9b7dd535a65d922cd108b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "927d4805aea0a287d36dd4f826ee24d69a2afee3",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
              "lessThan": "1c6267a1d5cf4c73b656f8181b310cbbb3e4767b",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/smb/client/smb2ops.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.19"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "4.19",
              "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/smb2ops.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-07-25T10:17:21.347",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/07e0ab81df1790afa35732a4e8e07ff831b29008",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1c6267a1d5cf4c73b656f8181b310cbbb3e4767b",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/297243e365fc9fe2f8e9b7dd535a65d922cd108b",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/67097772df7791c53d608f04bd31c676ccf79b83",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/68fc0b6cc03ca58060c0f36454e169f5fe258974",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9136a08dc29328edd9867f2545e73906ac9df93b",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/927d4805aea0a287d36dd4f826ee24d69a2afee3",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/94e4f672db029414b9888b5137a7559f1febf2d8",
      "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\nsmb: client: Fix next buffer leak in receive_encrypted_standard()\n\nreceive_encrypted_standard() allocates next_buffer before checking\nwhether the number of compound PDUs already reached MAX_COMPOUND. If\nthe limit check fails, the function returns immediately and the newly\nallocated next_buffer is not assigned to server->smallbuf/server->bigbuf,\nmaking it leaked.\n\nMove the MAX_COMPOUND check before allocating next_buffer."
    }
  ],
  "lastModified": "2026-09-08T14:01:34.767",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F611178E-6CBE-41F2-9F8B-E2F8651AF0F5",
              "versionEndExcluding": "5.10.261",
              "versionStartIncluding": "4.19"
            },
            {
              "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"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}