CVE-2026-14538: BigQuery Dataset Allowlist Bypass via Metadata Dry-Run in MCP Toolbox
Google · mcp-toolbox
Affected: Google mcp-toolbox · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 10% of scored CVEs
DescriptionCVE.org
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 products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- Google · mcp-toolboxfrom 0.16.1 up to and including 1.4.0
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CoverageNo articles yet
No CyberSIXT article names CVE-2026-14538 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.