CVE-2026-35577

{
  "id": "CVE-2026-35577",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-09T20:16:25.987",
  "lastModified": "2026-10-26T22:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Apollo MCP Server is a Model Context Protocol server that exposes GraphQL operations as MCP tools. Prior to version 1.7.0, the Apollo MCP Server did not validate the Host header on incoming HTTP requests when using StreamableHTTP transport. In configurations where an HTTP-based MCP server is run on localhost without additional authentication or network-level controls, this could potentially allow a malicious website—visited by a user running the server locally—to use DNS rebinding techniques to bypass same-origin policy restrictions and issue requests to the local MCP server. If successfully exploited, this could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the local user. This issue is limited to HTTP-based transport modes (StreamableHTTP). It does not affect servers using stdio transport. The practical risk is further reduced in deployments that use authentication, network-level access controls, or are not bound to localhost. This vulnerability is fixed in 1.7.0."
    },
    {
      "lang": "es",
      "value": "Apollo MCP Server es un servidor de Protocolo de Contexto de Modelo que expone operaciones GraphQL como herramientas MCP. Antes de la versión 1.7.0, el servidor Apollo MCP no validaba el encabezado Host en las solicitudes HTTP entrantes cuando utilizaba el transporte StreamableHTTP. En configuraciones donde un servidor MCP basado en HTTP se ejecuta en localhost sin autenticación adicional o controles a nivel de red, esto podría permitir potencialmente que un sitio web malicioso -visitado por un usuario que ejecuta el servidor localmente- utilice técnicas de reencuadernación de DNS para eludir las restricciones de la política del mismo origen y emitir solicitudes al servidor MCP local. Si se explota con éxito, esto podría permitir a un atacante invocar herramientas o acceder a recursos expuestos por el servidor MCP en nombre del usuario local. Este problema se limita a los modos de transporte basados en HTTP (StreamableHTTP). No afecta a los servidores que utilizan el transporte stdio. El riesgo práctico se reduce aún más en implementaciones que utilizan autenticación, controles de acceso a nivel de red o no están vinculadas a localhost. Esta vulnerabilidad se corrige en la versión 1.7.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "apollographql",
          "product": "apollo-mcp-server",
          "versions": [
            {
              "version": "< 1.7.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.2
      },
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N",
          "baseScore": 8.1,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-13T15:05:51.571445Z",
          "id": "CVE-2026-35577",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
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  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-346"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
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          "operator": "OR",
          "negate": false,
          "cpeMatch": [
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  "references": [
    {
      "url": "https://github.com/apollographql/apollo-mcp-server/pull/602",
      "source": "[email protected]",
      "tags": [
        "Issue Tracking"
      ]
    },
    {
      "url": "https://github.com/apollographql/apollo-mcp-server/pull/635",
      "source": "[email protected]",
      "tags": [
        "Issue Tracking"
      ]
    },
    {
      "url": "https://github.com/apollographql/apollo-mcp-server/security/advisories/GHSA-wqrj-vp8w-f8vh",
      "source": "[email protected]",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ]
    }
  ]
}