CVE-2026-87809

Siyuan before v3.8.2 fails to apply publish-access filtering to embedded blocks before rendering in the /api/export/preview and /api/lute/copyStdMarkdown endpoints. Attackers with reader access can retrieve the full rendered content of private, hidden, or publish-disabled blocks by accessing public documents containing embed queries that select those blocks.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8wx4-fvqw-f5f8
https://www.vulncheck.com/advisories/siyuan-before-3.8.2-information-disclosure-via-export-preview

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-09 12:17

Updated : 2026-09-09 20:20

NVD link : CVE-2026-87809

Mitre link : CVE-2026-87809

CVE.ORG link : CVE-2026-87809

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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