CVE-2026-66396: Siyuan-Note Siyuan

High severity, CVSS 8.4. EPSS: 0.5% chance of exploitation in the next 30 days.

SiYuan before v3.7.2 fails to escape the title-img Individual Attribute List value when rendering Gallery and Kanban cover images, allowing stored cross-site scripting via unescaped style attribute interpolation. Attackers with editor permissions can inject onload handlers that execute arbitrary code in the Electron renderer with full Node.js access when victims open affected documents.

Affected products

• Siyuan-Note Siyuan: before 3.7.2 (fixed in 3.7.2)

Published 2026-07-27. Last modified 2026-09-17.