CVE-2026-25536 — @modelcontextprotocol/sdk has cross-client data leak via shared server/transport instance reuse
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 Mc…
Published: 2026-02-04 · CVSS: 7.1 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7