CVE
CVE-2026-9739
MCP Toolbox for Databases vulnerable to DNS rebinding attacks
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.
Package Versions Affected
Package Version
patch Availability
No items found.
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.4
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-
Related Resources
No items found.
References
https://nvd.nist.gov/vuln/detail/CVE-2026-9739, https://github.com/googleapis/mcp-toolbox/issues/3053, https://github.com/googleapis/mcp-toolbox/pull/3054, https://github.com/googleapis/mcp-toolbox/commit/c4c7bd917e686de68e2be866cfe3872c3439efae, https://github.com/googleapis/mcp-toolbox