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CVE-2021-35211

Estado: AnalizadaCrítica (10)⚠ Explotación activa

Microsoft discovered a remote code execution (RCE) vulnerability in the SolarWinds Serv-U product utilizing a Remote Memory Escape Vulnerability. If exploited, a threat actor may be able to gain privileged access to the machine hosting Serv-U Only. SolarWinds Serv-U Managed File Transfer and Serv-U Secure FTP for Windows before 15.2.3 HF2 are affected by this vulnerability.

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).

CISA KEV — explotada activamente

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

RCE remoto sin autenticación (AV:N/PR:N/UI:N) en servicio expuesto SolarWinds Serv-U. Memoria desbordada (CWE-787) permite ejecución de código y acceso privilegiado comprobado en ataques ransomware activos.

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 ManagementUser Account ManagementExecution PreventionAuditUpdate SoftwareApplication Developer Guidance

Tecnologías afectadas (1)

Solarwinds — Serv-u

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2021-35211",
  "cveTags": [],
  "metrics": {
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      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-35211",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "active"
            },
            {
              "automatable": "no"
            },
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              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2025-02-04T19:06:30.616456Z"
        }
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    "cvssMetricV2": [
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          "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C",
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          "availabilityImpact": "COMPLETE",
          "confidentialityImpact": "COMPLETE"
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        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
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        "cvssData": {
          "scope": "CHANGED",
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          "attackVector": "NETWORK",
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          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
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        "cvssData": {
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      "affectedData": [
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          "versions": [
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              "version": "SolarWinds Serv-U",
              "lessThan": "15.2.3 HF1",
              "versionType": "custom"
            }
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          "platforms": [
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  ],
  "published": "2021-07-14T21:15:08.090",
  "references": [
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      "tags": [
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      "source": "psirt@solarwinds.com"
    },
    {
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      "tags": [
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      "source": "psirt@solarwinds.com"
    },
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
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      "tags": [
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-35211",
      "tags": [
        "US Government Resource"
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
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          "lang": "en",
          "value": "CWE-787"
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      ]
    },
    {
      "type": "Secondary",
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      "description": [
        {
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          "value": "CWE-787"
        }
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    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Microsoft discovered a remote code execution (RCE) vulnerability in the SolarWinds Serv-U product utilizing a Remote Memory Escape Vulnerability. If exploited, a threat actor may be able to gain privileged access to the machine hosting Serv-U Only. SolarWinds Serv-U Managed File Transfer and Serv-U Secure FTP for Windows before 15.2.3 HF2 are affected by this vulnerability."
    },
    {
      "lang": "es",
      "value": "Microsoft descubrió una vulnerabilidad de ejecución de código remota (RCE) en el producto SolarWinds Serv-U usando una Vulnerabilidad de Escape de Memoria Remota. Si es explotado, un actor de la amenaza puede ser capaz de obtener acceso privilegiado a la máquina que aloja Serv-U solamente. SolarWinds Serv-U Managed File Transfer y Serv-U Secure FTP para Windows versiones anteriores a 15.2.3 HF2 están afectados por esta vulnerabilidad"
    }
  ],
  "lastModified": "2026-06-17T03:57:18.450",
  "cisaActionDue": "2021-11-17",
  "cisaExploitAdd": "2021-11-03",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
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              "vulnerable": true,
              "matchCriteriaId": "66A68531-7831-4875-B0AB-215C3E5A62B6",
              "versionEndExcluding": "15.2.3"
            },
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          ],
          "operator": "OR"
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  ],
  "sourceIdentifier": "psirt@solarwinds.com",
  "cisaRequiredAction": "Apply updates per vendor instructions.",
  "cisaVulnerabilityName": "SolarWinds Serv-U Remote Code Execution Vulnerability"
}