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CVE-2026-6687

Estado: AnalizadaAlta (7.6)—

FatFs R0.16 and earlier contains a stack overflow bug in f_getlabel() because exFAT label length (XDIR_NumLabel) is trusted without enforcing spec maximums. This maps to CWE-121 (Stack-based Buffer Overflow). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (7.6, High). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.

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.

AV:P (acceso físico) requiere medios extraíbles con exFAT malformado. Stack overflow en f_getlabel() permite ejecución de código arbitrario (T1059) o denegación de servicio (T1499).

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

Behavior Prevention on EndpointDisable or Remove Feature or ProgramRestrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationLimit Hardware Installation

Tecnologías afectadas (1)

Elm-chan — Fatfs

CWE

Referencias

JSON original (NVD)

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{
  "id": "CVE-2026-6687",
  "cveTags": [],
  "metrics": {
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          "role": "CISA Coordinator",
          "options": [
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            },
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              "automatable": "no"
            },
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              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-07-01T15:06:20.995228Z"
        }
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          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
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  "published": "2026-07-01T15:17:12.870",
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  "descriptions": [
    {
      "lang": "en",
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    }
  ],
  "lastModified": "2026-07-02T14:38:40.173",
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}