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.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Sat, 13 Jun 2026 11:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Title | Model Context Protocol Allows DNS Rebinding Due to Origin Header Validation Failure |
Sat, 13 Jun 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Google
Google mcp Toolbox For Databases |
|
| Vendors & Products |
Google
Google mcp Toolbox For Databases |
Sat, 13 Jun 2026 09:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Weaknesses | CWE-346 | |
| References |
| |
| Metrics |
cvssV4_0
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Projects
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Status: PUBLISHED
Assigner: Google
Published:
Updated: 2026-06-13T08:38:42.908Z
Reserved: 2026-06-08T20:57:51.543Z
Link: CVE-2026-11624
No data.
Status : Received
Published: 2026-06-13T10:16:17.700
Modified: 2026-06-13T10:16:17.700
Link: CVE-2026-11624
No data.
OpenCVE Enrichment
Updated: 2026-06-13T11:00:07Z
Weaknesses