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CVE-2019-25634

Estado: AnalizadaAlta (8.6)—

Base64 Decoder 1.1.2 contains a stack-based buffer overflow vulnerability that allows local attackers to execute arbitrary code by triggering a structured exception handler (SEH) overwrite. Attackers can craft a malicious input file that overflows a buffer, overwrites the SEH chain with a POP-POP-RET gadget address, and uses an egghunter payload to locate and execute shellcode for code execution.

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.

Vulnerabilidad local (AV:L/PR:N) sin interacción que permite ejecución de código arbitrario mediante desbordamiento de buffer y sobrescritura SEH, típico de escalada de privilegios en Windows.

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

Execution PreventionThreat Intelligence ProgramRestrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationBehavior Prevention on Endpoint

Tecnologías afectadas (1)

4mhz — Base64 Decoder

CWE

Referencias

JSON original (NVD)

Mostrar
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          "role": "CISA Coordinator",
          "options": [
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              "automatable": "no"
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              "technicalImpact": "total"
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          "version": "2.0.3",
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          "valueDensity": "NOT_DEFINED",
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          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
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          "product": "Base64 Decoder",
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  "published": "2026-03-24T12:16:04.000",
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      "tags": [
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        "Release Notes"
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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          "value": "CWE-787"
        }
      ]
    }
  ],
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      "lang": "en",
      "value": "Base64 Decoder 1.1.2 contains a stack-based buffer overflow vulnerability that allows local attackers to execute arbitrary code by triggering a structured exception handler (SEH) overwrite. Attackers can craft a malicious input file that overflows a buffer, overwrites the SEH chain with a POP-POP-RET gadget address, and uses an egghunter payload to locate and execute shellcode for code execution."
    },
    {
      "lang": "es",
      "value": "Base64 Decoder 1.1.2 contiene una vulnerabilidad de desbordamiento de búfer basado en pila que permite a atacantes locales ejecutar código arbitrario al desencadenar una sobrescritura del gestor de excepciones estructuradas (SEH). Los atacantes pueden crear un archivo de entrada malicioso que desborda un búfer, sobrescribe la cadena SEH con una dirección de gadget POP-POP-RET y utiliza una carga útil egghunter para localizar y ejecutar shellcode para la ejecución de código."
    }
  ],
  "lastModified": "2026-06-17T02:32:51.460",
  "configurations": [
    {
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        {
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}