Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.6.34 until 0.11.0, Open WebUI renders vega and vega-lite fenced code blocks in chat content by building a Vega view in the viewer browser without a restricted resource loader. Any user who can place such a block where another user will see it can make that user browser issue attacker-chosen outbound GET requests and read responses from same-origin or CORS-permissive targets into the rendered page. This issue is fixed in 0.11.0.