CVE-2026-78660

Estado: Pendiente de análisisAlta (7.5)—

Históricamente, hemos sido bastante laxos con las cabeceras relacionadas con el entramado mal formadas en nuestra implementación de HTTP/2, ya que no pueden interferir con el entramado de HTTP/2. Sin embargo, esto hace posible que nuestra implementación de HTTP/2 reenvíe respuestas que contienen dichas cabeceras a un cliente HTTP/1 cuando actúa como proxy inverso. Si el cliente HTTP/1 tampoco se comporta de forma suficientemente estricta, esto puede dar lugar a contrabando de respuestas (response smuggling).

Traducción automática del texto original de NVD (en inglés).

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.30%
Percentil entre todas las CVEs puntuadas: 21
Fecha de la puntuación: 14/10/2026

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).

🎯 Técnicas ATT&CK

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

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1565.002 Transmitted Data Manipulationimpact75 %
Impacto secundarioT1499.004 Application or System Exploitationimpact65 %

AV:N/PR:N/UI:N indica red sin autenticación (T1190). HTTP/2 a HTTP/1 smuggling permite modificar respuestas (T1565.002) y potencial DoS por desincronización (T1499.004).

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

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Encrypt Sensitive Information

CWE

CWE-444

Referencias

JSON original (NVD)

Mostrar

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  "id": "CVE-2026-78660",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-78660",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-09T16:21:51.217328Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
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          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "security@golang.org",
      "affectedData": [
        {
          "vendor": "Go standard library",
          "product": "net/http",
          "versions": [
            {
              "status": "affected",
              "version": "0",
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              "versionType": "semver"
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          ],
          "packageName": "net/http",
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "programRoutines": [
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              "name": "http2clientConnReadLoop.handleResponse"
            },
            {
              "name": "Client.CloseIdleConnections"
            },
            {
              "name": "Client.Do"
            },
            {
              "name": "Client.Get"
            },
            {
              "name": "Client.Head"
            },
            {
              "name": "Client.Post"
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            {
              "name": "Client.PostForm"
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            {
              "name": "ClientConn.Close"
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            {
              "name": "ClientConn.RoundTrip"
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            {
              "name": "Get"
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            {
              "name": "Head"
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            {
              "name": "Post"
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              "name": "Transport.NewClientConn"
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            {
              "name": "Transport.RoundTrip"
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            {
              "name": "http1ClientConn.Close"
            },
            {
              "name": "http1ClientConn.RoundTrip"
            },
            {
              "name": "http2Transport.NewClientConn"
            },
            {
              "name": "http2Transport.RoundTrip"
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            {
              "name": "http2Transport.RoundTripOpt"
            },
            {
              "name": "http2clientConnPool.GetClientConn"
            },
            {
              "name": "http2noDialClientConnPool.GetClientConn"
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            {
              "name": "http2noDialH2RoundTripper.NewClientConn"
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            {
              "name": "http2noDialH2RoundTripper.RoundTrip"
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            {
              "name": "http2unencryptedTransport.RoundTrip"
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          "vendor": "Go standard library",
          "product": "net/http/internal/http2",
          "versions": [
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          "collectionURL": "https://pkg.go.dev",
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          "programRoutines": [
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              "name": "clientConnReadLoop.handleResponse"
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            {
              "name": "Transport.AddConn"
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            {
              "name": "Transport.NewClientConn"
            },
            {
              "name": "Transport.RoundTrip"
            },
            {
              "name": "Transport.RoundTripOpt"
            },
            {
              "name": "clientConnPool.GetClientConn"
            },
            {
              "name": "noDialClientConnPool.GetClientConn"
            }
          ]
        },
        {
          "vendor": "golang.org/x/net",
          "product": "golang.org/x/net/http2",
          "versions": [
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              "lessThan": "0.60.0",
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          "collectionURL": "https://pkg.go.dev",
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          "programRoutines": [
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              "name": "Transport.RoundTripOpt"
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              "name": "noDialH2RoundTripper.NewClientConn"
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              "name": "noDialH2RoundTripper.RoundTrip"
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              "name": "unencryptedTransport.RoundTrip"
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        }
      ]
    }
  ],
  "published": "2026-10-08T23:17:03.510",
  "references": [
    {
      "url": "https://go.dev/cl/835145",
      "source": "security@golang.org"
    },
    {
      "url": "https://go.dev/cl/836385",
      "source": "security@golang.org"
    },
    {
      "url": "https://go.dev/issue/81115",
      "source": "security@golang.org"
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    {
      "url": "https://groups.google.com/g/golang-announce/c/U2fTuyDJznI",
      "source": "security@golang.org"
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    {
      "url": "https://pkg.go.dev/vuln/GO-2026-6610",
      "source": "security@golang.org"
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  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
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      "value": "Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling."
    }
  ],
  "lastModified": "2026-10-09T17:16:49.243",
  "sourceIdentifier": "security@golang.org"
}