CVEvulnerability

CVE-2026-33252

6.5 MEDIUM Published 2026-03-24 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-24
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
7.1 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L
CVSS 3.1 ([email protected])
6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Weaknesses
CWE-352

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.

Affected configurations

• lfprojects mcp go sdk (< 1.4.1)

Related

Weakness · CWE (1)

  • CWE-352 Cross-Site Request Forgery weakness

References