CVE-2026-11719

An authenticated authorization bypass vulnerability exists in MCP Toolbox for Databases due to missing scope enforcement across older protocol handlers. While the 2025-11-25 protocol version handler correctly enforces per-tool restrictions defined by scopesRequired, older supported protocol versions (2025-06-18, 2025-03-26, and 2024-11-05) omit this check. An authenticated client with low-privilege tokens (e.g., read) can bypass the intended per-tool scope restrictions and execute high-privilege tools (e.g., admin) simply by specifying an older protocol version in the MCP-Protocol-Version header, or by omitting the header entirely (which causes the server to default to the vulnerable 2024-11-05 handler).

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/googleapis/mcp-toolbox/pull/3049	Patch
https://github.com/googleapis/mcp-toolbox/pull/3335	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:google:mcp_toolbox_for_databases:1.3.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-18 14:17

Updated : 2026-08-17 15:59

NVD link : CVE-2026-11719

Mitre link : CVE-2026-11719

CVE.ORG link : CVE-2026-11719

JSON object : View

Products Affected

google

mcp_toolbox_for_databases

CWE

CWE-862

Missing Authorization

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