CVE-2026-68586

SiYuan before v3.7.3 fails to apply publish-access filters to the getBacklinkDoc and getBackmentionDoc content endpoints (/api/ref/getBacklinkDoc and /api/ref/getBackmentionDoc). While the corresponding backlink list endpoints filter publish-forbidden documents, the content endpoints (gated only by CheckAuth) do not. A publish-mode reader — including an anonymous reader when publish Basic Auth is disabled — can call these endpoints directly with a publish-forbidden document's ID to retrieve its rendered DOM content and to determine whether the document references a given block (a reference-existence oracle).

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-36v8-mpjm-8j5r
https://www.vulncheck.com/advisories/siyuan-before-content-disclosure-via-getbacklinkdoc

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-03 14:16

Updated : 2026-08-26 17:06

NVD link : CVE-2026-68586

Mitre link : CVE-2026-68586

CVE.ORG link : CVE-2026-68586

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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