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CVE-2021-42321

Estado: AnalizadaAlta (8.8)⚠ Explotación activa💥 Exploit

Microsoft Exchange Server Remote Code Execution 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

💥 Exploits públicos

Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.

⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.

🎯 Técnicas ATT&CK

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

RCE en Exchange vía red (AV:N, PR:L) es T1210. La ejecución remota de código en servidor perimetral permite shell remoto, corrupción de datos y negación de servicio, confirmado por uso activo en ransomware.

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 ManagementDisable or Remove Feature or ProgramVulnerability ScanningThreat Intelligence ProgramRestrict File and Directory PermissionsRemote Data Storage

Tecnologías afectadas (1)

Microsoft — Exchange Server

CWE

Referencias

JSON original (NVD)

Mostrar
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          "options": [
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  "published": "2021-11-10T01:19:50.047",
  "references": [
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      "tags": [
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "description": [
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  "descriptions": [
    {
      "lang": "en",
      "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de Ejecución de Código Remota en Microsoft Exchange Server"
    }
  ],
  "lastModified": "2026-08-19T19:23:07.277",
  "cisaActionDue": "2021-12-01",
  "cisaExploitAdd": "2021-11-17",
  "configurations": [
    {
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}