CVE-2026-25536

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.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/modelcontextprotocol/typescript-sdk/issues/204	Issue Tracking Vendor Advisory
https://github.com/modelcontextprotocol/typescript-sdk/issues/243	Issue Tracking Vendor Advisory
https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-345p-7cg4-v4c7	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:lfprojects:mcp_typescript_sdk:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-02-04 22:15

Updated : 2026-03-18 14:22

NVD link : CVE-2026-25536

Mitre link : CVE-2026-25536

CVE.ORG link : CVE-2026-25536

JSON object : View

Products Affected

lfprojects

mcp_typescript_sdk

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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