MCP Go SDK Allows Cross-Site Tool Execution for HTTP Servers without Authorizatrion
Summary
MCP Go SDK Allows Cross-Site Tool Execution for HTTP Servers without Authorizatrion
Original description
The description as published by the source.
The Go MCP SDK used Go's standard encoding/json. Prior to version 1.4.1, the Go SDK's Streamable HTTP transport accepted browser-generated cross-site POST requests without validating the Origin header and without requiring Content-Type: application/json. In deployments without Authorization, especially stateless or sessionless configurations, this allows an arbitrary website to send MCP requests to a local server and potentially trigger tool execution. Version 1.4.1 contains a patch for the issue.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- patch github.com