CVSS7.6
Severityhigh
WeaknessCWE-79
ExploitedNot in CISA KEV
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
Description
Chartbrew is an open-source web application that can connect directly to databases and APIs and use the data to create charts. In versions 4.9.0 through 5.0.0, an authenticated user with project-editor permissions can store arbitrary HTML/JavaScript in the `ChartDatasetConfig.legend` field. The payload is persisted verbatim in the database, propagated through the Chart.js rendering pipeline, and injected into the tooltip DOM element via an unguarded `innerHTML` assignment in `ChartTooltip.js`. Every unauthenticated viewer of the public dashboard triggers JavaScript execution on page load — no hover interaction is required. Browser-based Playwright verification confirmed `alert('localhost')`