{"id":"CVE-2026-11717","revision":"f28b48c4d5d545c883c6c3ed30a3d823","records":[{"revision":"f28b48c4d5d545c883c6c3ed30a3d823","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-11717","aliases":[],"title":"An authentication bypass vulnerability exists in the generic opaque token validation path (validateOpaqueToken) of googleapis/mcp-toolbox.","description":"An authentication bypass vulnerability exists in the generic opaque token validation path (validateOpaqueToken) of googleapis/mcp-toolbox.\n\nWhen verifying an unparsed opaque token via an OAuth 2.0 introspection endpoint (RFC 7662), the toolbox decodes the response into an introspectResp struct where the Active field is declared as a pointer to a boolean (*bool). The code only explicitly rejects a token if the response contains a populated active field set to false (if introspectResp.Active != nil && !*introspectResp.Active). If an introspection endpoint responds with a payload that completely omits the mandatory active key, the internal variable remains nil, causing the conditional check to short-circuit. As a result, Toolbox accepts authorization tokens missing the \"active\" field, granting access to protected tools and underlying data sources.","state":0,"publishedAt":"2026-06-18T11:50:23.665+00:00","modifiedAt":"2026-06-18T12:23:15.209+00:00","affected":[{"ecosystem":"Vendor product","name":"MCP Toolbox for Databases (googleapis/mcp-toolbox)","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Google\",\n                    \"product\": \"MCP Toolbox for Databases (googleapis/mcp-toolbox)\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"1.0.0\",\n                            \"lessThanOrEqual\": \"1.3.0\",\n                            \"versionType\": \"semver\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\"\n                }"}],"metrics":[{"system":"CVSS 4.0","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","score":9.3,"severity":"CRITICAL"}],"references":["https://github.com/googleapis/mcp-toolbox/pull/3341"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-11717","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-11717","identifiers":["CVE-2026-11717"]},"retained":false,"historicalAffected":[]}],"coverage":[]}