- Add is_session_item field to ConfigItem type to control storage location
- Store auth tokens in sessionStorage (cleared on browser close)
- Store other settings in localStorage (persist between sessions)
- Maintain backward compatibility with existing config structure
This provides better security for auth tokens while preserving user
preferences across browser sessions.
- Update connection error message to guide users about proxy token configuration
- Add specific message when proxy token is missing directing to Configuration section
- Help users quickly identify and resolve authentication issues
- Auto-open browser only works when DANGEROUSLY_OMIT_AUTH=true
- When auth is enabled (default), users must use the secure URL with token
- Server displays clear message that auto-open is disabled with auth
- Updates documentation to reflect this behavior
This improves UX by preventing the browser from opening without auth token,
forcing users to use the secure pre-filled URL instead.
- Add origin validation middleware to check Origin header
- Default allowed origins respect CLIENT_PORT environment variable
- Support ALLOWED_ORIGINS environment variable for additional origins
- Apply validation to all protected endpoints before auth check
- Return 403 Forbidden with clear message for invalid origins
- Add DNS Rebinding Protection section to README
This completes the security hardening by preventing malicious websites
from making requests to the local proxy server.
- Add MCP_PROXY_AUTH_TOKEN configuration field to store session token
- Update useConnection hook to include proxy auth token in all requests
- Add separate proxy auth headers to avoid conflicts with MCP server auth
- Add specific error handling for proxy authentication failures
- Show helpful toast message directing users to Configuration settings
- Update README with instructions for configuring token in UI
The client now properly authenticates with the proxy server using the
session token displayed in the proxy console.
- Generate random session token on server startup using crypto.randomBytes
- Add authentication middleware requiring Bearer token for all sensitive endpoints
- Apply auth to /mcp, /stdio, /sse, and /message endpoints
- Display session token in console on startup
- Add DANGEROUSLY_OMIT_AUTH environment variable to disable auth for development
- Update README with authentication documentation
This prevents unauthorized access to the proxy server's ability to execute
local processes and connect to MCP servers.
- Change default binding from 0.0.0.0 (all interfaces) to 127.0.0.1 (localhost only)
- Add HOST environment variable to override binding address when needed
- Update console output to show actual binding address
- Document security change in README with warnings about binding to all interfaces
This prevents remote attackers from accessing the MCP Inspector proxy server,
which has the ability to execute local processes. The proxy should only be
accessible from the local machine unless explicitly configured otherwise.
* In server/src/index.ts
- slight format tweak of the Client <-> Proxy message so that the two messages will line up when displayed
* In server/src/mcpProxy.ts
- add reportedServerSession boolean initialized to false
- in transportToServer.onmessage,
- if reportedServerSession isn't set yet, report the sessionId if present on the transport, and then set reportedServerSession to true
* In server/index.js
- in createTransport()
- stringify query params to put them on one line
- remove logging of transport creation (done in callers)
- in /mcp POST handler
- report POST request if session id is present
- otherwise, report new StreamableHttp connection request
- report creation of server transport
- report creation of client transport
- in /stdio GET handler
- report new STDIO connection request
- report creation of server transport
- report creation of client transport
- report 401 as authentication error without stack
- in stderr data handler
- if it includes "MODULE_NOT_FOUND"
- report "Command not found"
- remove transports
- otherwise send to client as usual
- in /sse GET handler
- report SSE connection request
- report 401 as authentication error without stack
- report 404 as server that may not support SSE
- report error with "ECONNREFUSED" as "Connection refused" without stack
- only create, map, and proxy transports if serverTransport was successfully created
- in /message POST handler
- report received POST message
* In mcpProxy.ts
- in onServerError()
- if error message includes 404 OR error.cause includes ECONNREFUSED, report "Connection refused."