CVE-2026-105205: Exposure of Sensitive Information to an Unauthorized Actor in siyuan-note siyuan
Description
SiYuan note-taking software versions before 3.8.5 have an information disclosure vulnerability. This flaw allows users with publish-mode reader access to retrieve backlink block IDs and reference counts from documents that are password-protected or have publishing disabled. Attackers can exploit this by sending POST requests to specific API endpoints of published documents, thereby bypassing confidentiality controls.
CVSS v4.0
Score 6.9medium
Affected software
siyuan-note
siyuan
pkg:github/siyuan-note/siyuanRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-105205 describes an information disclosure vulnerability in SiYuan note-taking software versions prior to 3.8.5. The vulnerability permits publish-mode readers to query published documents via POST requests to /api/block/getDocInfo or getDocsInfo endpoints and obtain backlink block IDs and reference counts from documents that are supposed to be confidential (password-protected or publish-disabled). This results in exposure of sensitive metadata that should be inaccessible, effectively bypassing the publish confidentiality boundary.
Potential Impact
The vulnerability allows unauthorized disclosure of sensitive metadata about hidden referencing blocks within confidential documents. While it does not disclose the document content itself, the exposure of backlink IDs and reference counts can reveal structural information about the document and its references, potentially aiding further reconnaissance or targeted attacks. The CVSS 4.0 base score is 6.9, indicating a medium severity impact.
Mitigation Recommendations
A fixed version 3.8.5 or later is available that addresses this information disclosure issue. Users should upgrade to SiYuan version 3.8.5 or newer to remediate this vulnerability. No other mitigation steps are indicated or necessary once the update is applied.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-10-04T13:02:21.188Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ac265f312601ec6a324ce4e
Added to database: 10/04/2026, 14:42:59 UTC
Last enriched: 10/04/2026, 14:57:46 UTC
Last updated: 10/04/2026, 16:16:14 UTC
Views: 7
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