@modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuse_CVE-2026-25536

{
    "lastseen": "",
    "description": "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.",
    "published": "2026-02-04T21:29:38.276Z",
    "modified": "2026-02-04T21:29:38.276Z",
    "type": "cve",
    "title": "@modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuse",
    "source": "GitHub_M",
    "references": "https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-345p-7cg4-v4c7\nhttps://github.com/modelcontextprotocol/typescript-sdk/issues/204\nhttps://github.com/modelcontextprotocol/typescript-sdk/issues/243",
    "id": "CVE-2026-25536",
    "bulletinFamily": "",
    "cwe": [
        "CWE-362"
    ],
    "cvelist": null,
    "sourceData": "modelcontextprotocol typescript-sdk >= 1.10.0, < 1.26.0",
    "sourceHref": "",
    "cvss": {
        "score": 7.1,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
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            "privilegesRequired": "",
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        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "typescript-sdk",
    "version": ">= 1.10.0, < 1.26.0",
    "vendor": "modelcontextprotocol",
    "ai_description": "",
    "ai_severity": "",
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    "ai_product": "",
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    "ai_score": 0
}