CVE-2026-111770

The Model Context Protocol TypeScript SDK provides TypeScript client and server implementations of the Model Context Protocol. From 2.0.0 until 2.3.0 in @modelcontextprotocol/server, applications that shared one stateless HTTP transport or one McpServer or Server instance among multiple clients...

MCP TypeScript server SDK: Shared transport or server instances delivered one HTTP client's messages to another

Summary In affected versions, an MCP server reached over HTTP could deliver one client's responses and notifications to another client. This happened when clients shared one stateless transport, or one McpServer or Server instance. Messages were matched to a connection by JSON-RPC id alone. SDK...

GHSA-JM63-CQ47-J5JP MCP TypeScript server SDK: Shared transport or server instances delivered one HTTP client's messages to another

Summary In affected versions, an MCP server reached over HTTP could deliver one client's responses and notifications to another client. This happened when clients shared one stateless transport, or one McpServer or Server instance. Messages were matched to a connection by JSON-RPC id alone. SDK...

PT-2026-120151

Name of the Vulnerable Software and Affected Versions @modelcontextprotocol/server versions 2.0.0 through 2.2.0 Description An MCP server accessed over HTTP may deliver responses and notifications from one client to another. This occurs when clients share a single stateless transport, McpServer...

PT-2026-120314

Summary In affected versions, an MCP server reached over HTTP could deliver one client's responses and notifications to another client. This happened when clients shared one stateless transport, or one McpServer or Server instance. Messages were matched to a connection by JSON-RPC id alone. SDK...