Vulnerability · Published Jun 18, 2026 · Assigned by Google
CVE-2026-11719
High 8.6
In plain English
A high-severity missing authorization in MCP Toolbox for Databases (googleapis/mcp-toolbox) from Google. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
An authenticated authorization bypass vulnerability exists in MCP Toolbox for Databases due to missing scope enforcement across older protocol handlers. While the 2025-11-25 protocol version handler correctly enforces per-tool restrictions defined by scopesRequired, older supported protocol versions (2025-06-18, 2025-03-26, and 2024-11-05) omit this check. An authenticated client with low-privilege tokens (e.g., read) can bypass the intended per-tool scope restrictions and execute high-privilege tools (e.g., admin) simply by specifying an older protocol version in the MCP-Protocol-Version header, or by omitting the header entirely (which causes the server to default to the vulnerable 2024-11-05 handler).
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/googleapis/mcp-toolbox | 1.4.0 | GHSA-5gf6-gc35-xjpc |
| Go | github.com/googleapis/mcp-toolbox | 1.4.0 | GO-2026-5144 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| MCP Toolbox for Databases (googleapis/mcp-toolbox) | 1.3.0 |
Weakness: CWE-862 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N