Google MCP Toolbox for Databases up to 1.2.x Relative URL /api/v1/users path traversal

Summaryinfo

A vulnerability was found in Google MCP Toolbox for Databases up to 1.2.x. It has been declared as critical. Affected by this vulnerability is an unknown functionality of the file /api/v1/users of the component Relative URL Handler. Such manipulation leads to path traversal. This vulnerability is referenced as CVE-2026-11720. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Google MCP Toolbox for Databases up to 1.2.x. It has been rated as critical. Affected by this issue is some unknown processing of the file /api/v1/users of the component Relative URL Handler. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A path traversal vulnerability exists in the HTTP tool URL builder of googleapis/mcp-toolbox. When constructing downstream API requests, the URL builder substitutes user-controlled pathParams into the configured tool path and parses the resulting string as a relative URL. While it checks that the input does not alter the scheme, host, or user info, it relies on ResolveReference for the final URL resolution. Because dot segments (../) are normalized during this resolution step, an attacker can supply path parameters containing directory traversal sequences to escape the operator-configured path scope. This allows the client to coerce the toolbox into making requests to unintended endpoints on the same target host while forwarding the toolbox's configured credentials (e.g., bypassing a restricted path like /api/v1/users/{{.id}} to reach /admin/secrets).

The weakness was published by Ryan Vonbrubeck and @dodge1218. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-11720 since 06/09/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/29/2026). The MITRE ATT&CK project declares the attack technique as T1006.

Upgrading to version 1.3.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• Google

Name

• MCP Toolbox for Databases

Version

• 1.0
• 1.1
• 1.2

License

• free

Website

• Vendor: https://www.google.com/

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