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CVE-2021-33500

Estado: ModificadaAlta (7.5)—

PuTTY before 0.75 on Windows allows remote servers to cause a denial of service (Windows GUI hang) by telling the PuTTY window to change its title repeatedly at high speed, which results in many SetWindowTextA or SetWindowTextW calls. NOTE: the same attack methodology may affect some OS-level GUIs on Linux or other platforms for similar reasons.

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).

Tecnologías afectadas (1)

Putty — Putty

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2021-33500",
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          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "NONE"
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        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
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        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
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  "vulnStatus": "Modified",
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      "lang": "en",
      "value": "PuTTY before 0.75 on Windows allows remote servers to cause a denial of service (Windows GUI hang) by telling the PuTTY window to change its title repeatedly at high speed, which results in many SetWindowTextA or SetWindowTextW calls. NOTE: the same attack methodology may affect some OS-level GUIs on Linux or other platforms for similar reasons."
    },
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      "value": "PuTTY versiones anteriores a 0.75, en Windows permite a servidores remotos causar una denegación de servicio (colgar la GUI de Windows) al indicar a la ventana de PuTTY que cambie su título repetidamente a gran velocidad, lo que resulta en muchas llamadas a SetWindowTextA o SetWindowTextW. NOTA: la misma metodología de ataque puede afectar a algunas interfaces gráficas de usuario en Linux y otras plataformas por razones similares"
    }
  ],
  "lastModified": "2026-06-17T03:54:41.047",
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