CVE-2026-14541

An authentication bypass and audience confusion vulnerability exists in the Google OAuth provider component of Google mcp-toolbox version 1.4.0. When a Google authService is initialized with mcpEnabled: true but lacks an explicitly defined audience or clientId, the ValidateMCPAuth pipeline for opaque tokens skips audience validation entirely. As a result, the toolbox will accept any valid Google OAuth access token—even those minted for unrelated ecosystem applications—granting unauthorized clients access to protected tools and data backends.

CVSS

No CVSS.

References

Link	Resource
https://github.com/googleapis/mcp-toolbox/pull/3450

Configurations

No configuration.

History

31 Jul 2026, 03:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-31 03:16

Updated : 2026-07-31 17:16

NVD link : CVE-2026-14541

Mitre link : CVE-2026-14541

CVE.ORG link : CVE-2026-14541

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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