How severe is CVE-2026-14541?

CVE-2026-14541 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-14541 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-14541?

CVE-2026-14541 affects Google Mcp Toolbox For Databases. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-14541?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-14541 published?

CVE-2026-14541 was published on 2026-07-31 and last updated on 2026-08-08.

CVE-2026-14541

CVE-2026-14541 is a high-severity vulnerability in Google Mcp Toolbox For Databases with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.0
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Google Mcp Toolbox For Databases
Published: 2026-07-31
Last modified: 2026-08-08

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-14541?: CVE-2026-14541 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-14541 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-14541?: CVE-2026-14541 affects Google Mcp Toolbox For Databases. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-14541?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-14541 published?: CVE-2026-14541 was published on 2026-07-31 and last updated on 2026-08-08.

References

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

Affected products (1)

cpe:2.3:a:google:mcp_toolbox_for_databases:1.4.0:*:*:*:*:*:*:*

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