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CVE-2026-56855

Estado: AnalizadaAlta (7.5)—

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

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.

Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Tecnologías afectadas (1)

CWE

Referencias

JSON original (NVD)

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{
  "id": "CVE-2026-56855",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-56855",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-09-03T14:13:54.397574Z"
        }
      }
    ],
    "cvssMetricV31": [
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
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        "exploitabilityScore": 3.9
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  "affected": [
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          "collectionURL": "https://pkg.go.dev",
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          "programRoutines": [
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              "name": "NewControlClientConn"
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  "published": "2026-09-02T20:17:36.397",
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      "url": "https://go.dev/cl/826524",
      "tags": [
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      "tags": [
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    {
      "url": "https://groups.google.com/g/golang-announce/c/1y3fb2np35U",
      "tags": [
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        "Vendor Advisory"
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      "source": "security@golang.org"
    },
    {
      "url": "https://pkg.go.dev/vuln/GO-2026-6355",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@golang.org"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "description": [
        {
          "lang": "en",
          "value": "CWE-770"
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      ]
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  "descriptions": [
    {
      "lang": "en",
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    }
  ],
  "lastModified": "2026-09-04T16:34:56.823",
  "configurations": [
    {
      "nodes": [
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          "negate": false,
          "cpeMatch": [
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              "versionEndExcluding": "0.56.0"
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          "operator": "OR"
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  ],
  "sourceIdentifier": "security@golang.org"
}