CVE-2026-33252 - MCP Go SDK Allows Cross-Site Tool Execution for HTTP Servers without Authorizatrion
CVE ID :CVE-2026-33252
Published : March 24, 2026, 12:16 a.m. | 46 minutes ago
Description :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.
Severity: 7.1 | HIGH
Visit the link for more details, such as CVSS details, affected products, timeline, and more...
Published : March 24, 2026, 12:16 a.m. | 46 minutes ago
Description :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.
Severity: 7.1 | HIGH
Visit the link for more details, such as CVSS details, affected products, timeline, and more...