CVE-2026-70492 Open WebUI: Stored XSS via unescaped KaTeX render-error fallback in rendered messages

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.0, src/lib/components/chat/Messages/Markdown/KatexRenderer.svelte could store and render a chat message whose math block makes KaTeX fail with a stack overflow instead of a parse error. Th...