Race Condition

Overview @modelcontextprotocol/sdk is a Model Context Protocol implementation for TypeScript Affected versions of this package are vulnerable to Race Condition via the reuse of a single McpServer or Server instance and transport across multiple concurrent client connections. An attacker can acces...

PT-2026-6350

Summary 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. Impact Who is affected: Any MCP server deployment using the TypeScript SDK where a sing...