CVE-2026-66394
SiYuan before v3.7.3 Stored and Reflected XSS via SVG Sanitizer Bypass
CVSS Score
8.7
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-79 |
| Vendor | siyuan-note |
| Product | siyuan |
| Published | Jul 27, 2026 |
Stay Ahead of the Next One
Get instant alerts for siyuan-note siyuan
Be the first to know when new high vulnerabilities affecting siyuan-note siyuan are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
siyuan-note / siyuan
0 < 3.7.3
References
Credits
🔍 JoyGhoshs