CVE-2026-23847: b3log Siyuan

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

SiYuan is a personal knowledge management system. Versions prior to 3.5.4 are vulnerable to reflected cross-site scripting in /api/icon/getDynamicIcon due to unsanitized SVG input. The endpoint generates SVG images for text icons (type=8). The content query parameter is inserted directly into the SVG <text> tag without XML escaping. Since the response Content-Type is image/svg+xml, injecting unescaped tags allows breaking the XML structure and executing JavaScript. Version 3.5.4 patches the issue.]

Affected products

• b3log Siyuan: before 3.5.4 (fixed in 3.5.4)

Published 2026-01-19. Last modified 2026-06-17.