CVE-2026-33946

{
  "id": "CVE-2026-33946",
  "sourceIdentifier": "[email protected]",
  "published": "2026-03-27T22:16:21.580",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to version 0.9.2, the Ruby SDK's streamable_http_transport.rb implementation contains a session hijacking vulnerability. An attacker who obtains a valid session ID can completely hijack the victim's Server-Sent Events (SSE) stream and intercept all real-time data. Version 0.9.2 contains a patch."
    },
    {
      "lang": "es",
      "value": "MCP Ruby SDK es el SDK oficial de Ruby para servidores y clientes del Protocolo de Contexto de Modelo. Antes de la versión 0.9.2, la implementación streamable_http_transport.rb del SDK de Ruby contiene una vulnerabilidad de secuestro de sesión. Un atacante que obtiene un ID de sesión válido puede secuestrar completamente el flujo de Eventos Enviados por el Servidor (SSE) de la víctima e interceptar todos los datos en tiempo real. La versión 0.9.2 contiene un parche."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "modelcontextprotocol",
          "product": "ruby-sdk",
          "versions": [
            {
              "version": "< 0.9.2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
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          "baseSeverity": "HIGH",
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          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
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          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
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          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
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          "modifiedAttackRequirements": "NOT_DEFINED",
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          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
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          "scope": "UNCHANGED",
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  "references": [
    {
      "url": "https://github.com/modelcontextprotocol/csharp-sdk/blob/main/src/ModelContextProtocol.AspNetCore/SseHandler.cs#L93-L97",
      "source": "[email protected]",
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    {
      "url": "https://github.com/modelcontextprotocol/go-sdk/blob/main/mcp/streamable.go#L281C1-L288C2",
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}