VULNERABILITY INTELLIGENCE

CVE-2026-14541

CVSS score7.5 HIGH
EPSS probability0.25%
CISA KEVNot currently listed
Published2026-07-31
Last modified2026-10-23
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Description

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.

Weakness classification

  • cve-coordination@google.com: CWE-287

Primary references