CVE-2026-33252 (GCVE-0-2026-33252)
Vulnerability from cvelistv5
Published
2026-03-23 23:44
Modified
2026-03-24 18:39
CWE
  • CWE-352 - Cross-Site Request Forgery (CSRF)
Summary
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.
Impacted products
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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