CVE-2026-6643

Estado: AnalizadaAlta (8.6)—

A stack-based buffer overflow vulnerability was found in the VPN Clients on the ADM. The issue stems from the use of unbounded sscanf() and passing user-controlled data directly to printf(). Due to the lack of PIE and Stack Canary protections, an authenticated remote attacker can exploit these to execute arbitrary code as the web server user. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RR42 as well as from ADM 5.0.0 through ADM 5.1.2.REO1.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 8.6

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.76%
Percentil entre todas las CVEs puntuadas: 54
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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement90 %
Impacto principalT1059 Command and Scripting Interpreterexecution85 %

Vector AV:N/PR:H indica red con privilegios; buffer overflow (CWE-121) en VPN permite ejecución de código arbitrario como usuario web servidor.

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

Privileged Account Management Disable or Remove Feature or Program Vulnerability Scanning Threat Intelligence Program Restrict Web-Based Content Network Segmentation

Tecnologías afectadas (1)

Asustor — Data Master

CWE

CWE-121

Referencias

https://www.asustor.com/security/security_advisory_detail?id=54

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-6643",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-6643",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-04-20T13:20:51.858306Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 9.9,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/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": 3.1
      }
    ],
    "cvssMetricV40": [
      {
        "type": "Secondary",
        "source": "security@asustor.com",
        "cvssData": {
          "Safety": "NOT_DEFINED",
          "version": "4.0",
          "Recovery": "NOT_DEFINED",
          "baseScore": 8.6,
          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "exploitMaturity": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "HIGH",
          "subIntegrityImpact": "LOW",
          "vulnIntegrityImpact": "HIGH",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "subAvailabilityImpact": "LOW",
          "vulnAvailabilityImpact": "HIGH",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "LOW",
          "vulnConfidentialityImpact": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
        }
      }
    ]
  },
  "affected": [
    {
      "source": "security@asustor.com",
      "affectedData": [
        {
          "vendor": "ASUSTOR Inc.",
          "product": "ADM",
          "versions": [
            {
              "status": "affected",
              "version": "4.1.0",
              "versionType": "custom",
              "lessThanOrEqual": "4.3.3.RR42"
            },
            {
              "status": "affected",
              "version": "5.0.0",
              "versionType": "custom",
              "lessThanOrEqual": "5.1.2.REO1"
            }
          ],
          "platforms": [
            "Linux",
            "x86",
            "ARM",
            "64 bit"
          ],
          "packageName": "VPN Clients",
          "defaultStatus": "unaffected"
        }
      ]
    }
  ],
  "published": "2026-04-20T07:16:16.543",
  "references": [
    {
      "url": "https://www.asustor.com/security/security_advisory_detail?id=54",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@asustor.com"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security@asustor.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-121"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A stack-based buffer overflow vulnerability was found in the VPN Clients on the ADM. The issue stems from the use of unbounded sscanf() and passing user-controlled data directly to printf(). Due to the lack of PIE and Stack Canary protections, an authenticated remote attacker can exploit these to execute arbitrary code as the web server user. \nAffected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RR42 as well as from ADM 5.0.0 through ADM 5.1.2.REO1."
    }
  ],
  "lastModified": "2026-06-17T11:01:08.593",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:asustor:data_master:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "20307258-479E-4ECD-AF5E-B31019D22525",
              "versionEndExcluding": "4.3.3.RR42",
              "versionStartIncluding": "4.1.0.rhu2"
            },
            {
              "criteria": "cpe:2.3:o:asustor:data_master:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "47B926F1-1D8F-4105-A533-45E0B4178C59",
              "versionEndExcluding": "5.1.2.reo1",
              "versionStartIncluding": "5.0.0.ra82"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security@asustor.com"
}