Description
SiYuan is a personal knowledge management system. In versions 3.6.0 and below, SanitizeSVG has an incomplete blocklist — it blocks data:text/html and data:image/svg+xml in href attributes but misses data:text/xml and data:application/xml, both of which can render SVG with JavaScript execution. The unauthenticated /api/icon/getDynamicIcon endpoint serves user-controlled input (via the content parameter) directly into SVG markup using fmt.Sprintf with no escaping, served as Content-Type: image/svg+xml. This creates a click-through XSS: a victim navigates to a crafted URL, sees an SVG with an injected link, and clicking it triggers JavaScript via the bypassed MIME types. The attack requires direct navigation to the endpoint or <object>/<embed> embedding, since <img> tag rendering in the frontend doesn't allow interactive links. This issue has been fixed in version 3.6.1.
Problem types
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-184: Incomplete List of Disallowed Inputs
Product status
References
github.com/...siyuan/security/advisories/GHSA-4mx9-3c2h-hwhg
github.com/...ommit/d01d561875d4f744e9f6232f1d4831e3642b8696
github.com/advisories/GHSA-6865-qjcf-286f
github.com/siyuan-note/siyuan/releases/tag/v3.6.1