Path Traversal in googleapis/mcp-toolbox HTTP Tool URL Builder_CVE-2026-11720

{
    "lastseen": "",
    "description": "A path traversal vulnerability exists in the HTTP tool URL builder of googleapis/mcp-toolbox.\n\nWhen 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).",
    "published": "2026-06-29T17:51:30.077Z",
    "modified": "2026-06-29T17:51:30.077Z",
    "type": "cve",
    "title": "Path Traversal in googleapis/mcp-toolbox HTTP Tool URL Builder",
    "source": "Google",
    "references": "https://github.com/googleapis/mcp-toolbox/pull/3218",
    "id": "CVE-2026-11720",
    "bulletinFamily": "",
    "cwe": [
        "CWE-22"
    ],
    "cvelist": null,
    "sourceData": "Google MCP Toolbox for Databases (googleapis/mcp-toolbox) 0",
    "sourceHref": "",
    "cvss": {
        "score": 9.3,
        "severity": "CRITICAL",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
        "version": "4.0"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "MCP Toolbox for Databases (googleapis/mcp-toolbox)",
    "version": "0",
    "vendor": "Google",
    "ai_description": "Path traversal vulnerability in googleapis/mcp-toolbox HTTP tool URL builder allowing unintended endpoint access",
    "ai_severity": "Critical",
    "ai_vendor": "Google",
    "ai_product": "MCP Toolbox for Databases (googleapis/mcp-toolbox)",
    "ai_version": "0",
    "ai_score": 9.3
}