VULNERABILITY INTELLIGENCE
CVE-2026-66394
CVSS score8.7 HIGH
EPSS probability0.34%
CISA KEVNot currently listed
Published2026-07-27
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
Description
SiYuan before v3.7.3 contains stored and reflected cross-site scripting vulnerabilities in SVG sanitization that allows authenticated attackers to execute scripts by bypassing the HTML parser-based cleaner. Attackers can hide script tags within desc, style, or noscript elements which the HTML parser treats as raw text but browsers interpret as executable SVG content when served as image/svg+xml, enabling script execution in the application origin.
Weakness classification
- disclosure@vulncheck.com: CWE-79