CVE-2016-8740

Estado: ModificadaAlta (7.5)—💥 Exploit
The mod_http2 module in the Apache HTTP Server 2.4.17 through 2.4.23, when the Protocols configuration includes h2 or h2c, does not restrict request-header length, which allows remote attackers to cause a denial of service (memory consumption) via crafted CONTINUATION frames in an HTTP/2 request.
CVSS

Versión: 3.0
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Puntuación base: 7.5
Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 79%
Percentil entre todas las CVEs puntuadas: 100
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).
💥 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.
Publicado en Exploit-DB · Apache 2.4.23 mod_http2 - Denial of Service (12/12/2016)
Prueba de concepto en GitHub (no verificada) · Lista de pruebas de concepto en GitHub
⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.
Tecnologías afectadas (1)

Apache — Http Server
CWE

CWE-20, CWE-399
Referencias

JSON original (NVD)

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          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
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          "value": "CWE-20"
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  "lastModified": "2026-06-17T00:54:55.280",
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