CVE-2026-105205: Siyuan-Note Siyuan

Medium severity, CVSS 5.3. EPSS: 0.2% chance of exploitation in the next 30 days.

SiYuan before 3.8.5 contains an information disclosure vulnerability that allows publish-mode readers to learn backlink block IDs and reference counts from password-protected and publish-disabled documents by querying a published document. Attackers can send POST requests to /api/block/getDocInfo or getDocsInfo for a published document ID to obtain refIDs and refCount of hidden referencing blocks, bypassing the publish confidentiality boundary.

Affected products

• Siyuan-Note Siyuan: before 3.8.5 (fixed in 3.8.5)

Published 2026-10-04. Last modified 2026-10-05.