CVE-2026-11720
Severity CVSS v4.0:
CRITICAL
Type:
CWE-22
Path Traversal
Publication date:
29/06/2026
Last modified:
01/07/2026
Description
A path traversal vulnerability exists in the HTTP tool URL builder of googleapis/mcp-toolbox.<br />
<br />
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&#39;s configured credentials (e.g., bypassing a restricted path like /api/v1/users/{{.id}} to reach /admin/secrets).
Impact
Base Score 4.0
9.30
Severity 4.0
CRITICAL
Base Score 3.x
9.10
Severity 3.x
CRITICAL
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:google:mcp_toolbox_for_databases:*:*:*:*:*:*:*:* | 1.3.0 (excluding) |
To consult the complete list of CPE names with products and versions, see this page