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CVE-2026-14541: google mcp_toolbox_for_databases Improper Authentication

CVSS: 8.0v4.0HighAnalyzed
Published 31-07-2026Last modified 31-07-2026
Open JSON

Vulnerability summary

CVE-2026-14541 is a high (CVSS 8.0) Improper Authentication vulnerability in google mcp_toolbox_for_databases. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.6% of scored vulnerabilities.

Overall risk
32/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.0/10
010
High · v4.0 (CVE.org)
EPSS score
0.25%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 31-07-2026
    PublishedVulnerability first disclosed.
  2. 31-07-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.25%

Chance of exploitation in the next 30 days

Percentile

16%

Versus all other CVEs

30-day change

+0.02 pp

From 0.23% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.25%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Google2 products

1 vendor · 2 products

References

1 links