CVE-2026-11624

The Model Context Protocol has a security warning advising servers to validate the "Origin" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin's host. In v0.25.0, a new "--allowed-hosts" flag was introduced alongside the existing "--allowed-origins" flag, enabling users to specify permitted hosts at server startup. Both flags default to "*", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to "*", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations.

CVSS

No CVSS.

References

Link	Resource
https://github.com/googleapis/mcp-toolbox/issues/3113
https://github.com/googleapis/mcp-toolbox/pull/2254

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-13 10:16

Updated : 2026-07-23 09:10

NVD link : CVE-2026-11624

Mitre link : CVE-2026-11624

CVE.ORG link : CVE-2026-11624

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

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