FKIE_CVE-2026-25536

Vulnerability from fkie_nvd - Published: 2026-02-04 22:15 - Updated: 2026-03-18 14:22
Severity ?
7.1 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Summary
MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. From version 1.10.0 to 1.25.3, cross-client response data leak when a single McpServer/Server and transport instance is reused across multiple client connections, most commonly in stateless StreamableHTTPServerTransport deployments. This issue has been patched in version 1.26.0.
References
security-advisories@github.comhttps://github.com/modelcontextprotocol/typescript-sdk/issues/204Issue Tracking, Vendor Advisory
security-advisories@github.comhttps://github.com/modelcontextprotocol/typescript-sdk/issues/243Issue Tracking, Vendor Advisory
security-advisories@github.comhttps://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-345p-7cg4-v4c7Mitigation, Vendor Advisory
Impacted products
Vendor Product Version
lfprojects mcp_typescript_sdk *
To clipboard 

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    {
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            {
              "criteria": "cpe:2.3:a:lfprojects:mcp_typescript_sdk:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B979E384-46FC-45C2-947D-62860FC1F257",
              "versionEndExcluding": "1.26.0",
              "versionStartIncluding": "1.10.0",
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            }
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          "negate": false,
          "operator": "OR"
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. From version 1.10.0 to 1.25.3, cross-client response data leak when a single McpServer/Server and transport instance is reused across multiple client connections, most commonly in stateless StreamableHTTPServerTransport deployments. This issue has been patched in version 1.26.0."
    },
    {
      "lang": "es",
      "value": "El SDK de TypeScript de MCP es el SDK oficial de TypeScript para servidores y clientes de Model Context Protocol. Desde la versi\u00f3n 1.10.0 hasta la 1.25.3, se produce una fuga de datos de respuesta entre clientes cuando una \u00fanica instancia de McpServer/servidor y de transporte es reutilizada a trav\u00e9s de m\u00faltiples conexiones de cliente, m\u00e1s com\u00fanmente en despliegues de StreamableHTTPServerTransport sin estado. Este problema ha sido parcheado en la versi\u00f3n 1.26.0."
    }
  ],
  "id": "CVE-2026-25536",
  "lastModified": "2026-03-18T14:22:25.350",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 4.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-02-04T22:15:59.663",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Issue Tracking",
        "Vendor Advisory"
      ],
      "url": "https://github.com/modelcontextprotocol/typescript-sdk/issues/204"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
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        "Vendor Advisory"
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    },
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      "source": "security-advisories@github.com",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ],
      "url": "https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-345p-7cg4-v4c7"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-362"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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