Chartbrew is an open-source web application that can connect directly to databases and APIs and use the data to create charts. In version 4.9.0, Chartbrew exposes POST /api/chart/:chart_id/query without authentication. The endpoint only checks team.allowReportRefresh and does not verify that the target chart belongs to a public report, that the project is public, or that sharing policy allows the operation. An unauthenticated attacker who knows a chart identifier can trigger a data refresh and retrieve the current data of private charts. This issue has been patched in version 5.0.0.