CVE-2026-33066: SiYuan has Stored XSS to RCE via Unsanitized Bazaar README Rendering

SiYuan’s Bazaar (community marketplace) renders package README content without HTML sanitization. The backend renderREADME function uses lute.New() without calling SetSanitize(true), allowing raw HTML embedded in Markdown to pass through unmodified. The frontend then assigns the rendered HTML to innerHTML without any additional sanitization. A malicious package author can embed arbitrary JavaScript in their README that executes when a user clicks to view the package details. Because SiYuan’s Electron configuration enables nodeIntegration: true with contextIsolation: false, this XSS escalates directly to full Remote Code Execution.