cvedb.io
CVE-2026-9739
UNKNOWN · CVSS n/a
EPSS exploitation probability: 0%
Published 2026-05-27T23:16:48.573 · Last modified 2026-06-17T11:05:36.330

Summary

Vulnerable to DNS rebinding attacks when using SSE (http://b/499408790). During the beta phase, we implemented `allowed-origins` and `allowed-hosts` flags to align with MCP security guidelines. However, the hardcoded `Access-Control-Allow-Origin: *` header in the SSE initialization handler was inadvertently retained. This vulnerability specifically impacts users connecting via Toolbox using SSE under specification v2024-11-05.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.