5.7
Medium
CVE-2026-14538 An improper authorization and security-boundary bypass vulnerability in the bigquery-execute-sql tool component of…
Description
An improper authorization and security-boundary bypass vulnerability in the bigquery-execute-sql tool component of Google mcp-toolbox versions 0.16.1 through 1.4.0 allows an authenticated attacker to bypass allowedDatasets validation checks. The toolbox relies on the BigQuery dry-run API to enforce dataset restrictions, but due to a fail-open logic flaw, it bypasses validation when the API returns an empty array for specialized constructs. This allows the attacker to extract structural DDL schemas for explicitly excluded datasets via INFORMATION_SCHEMA, and access downstream federated row data via EXTERNAL_QUERY connections.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| mcp-toolbox 0.16 | 0.16.1 → 1.4.0 | No fix stated |
References
- github.com github.com
Timeline
- Published
- Last modified
Other CVEs of mcp-toolbox
The 5 CVEs of mcp-toolbox →
CVE-2026-14541
An authentication bypass and audience confusion vulnerability exists in the Google OAuth provider component of Google…
8.0
High
CVE-2026-14540
A Server-Side Request Forgery (SSRF) vulnerability exists in the generic HTTP source and tool components of Google…
8.0
High
CVE-2026-14539
An allocation of resources without limits vulnerability in the HTTP handler component of Google mcp-toolbox versions…
6.6
Medium
CVE-2026-14537
Incorrect Authorization in the direct HTTP API tool invocation endpoint in Google mcp-toolbox versions v1.3.0 and v1.4.0…
8.1
High