CVE-2026-72812

SiYuan versions before v3.7.4 contain a missing authorization vulnerability in the /api/ref/refreshBacklink endpoint that allows anonymous readers to trigger persistent server-side writes. Attackers can invoke the endpoint with an attacker-controlled block ID to flush transaction queues, scan all references globally, and enqueue database writes, bypassing read-only protections and enabling resource amplification attacks.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wgwx-479j-23vq
https://www.vulncheck.com/advisories/siyuan-before-missing-authorization-via-refreshbacklink

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-14 12:16

Updated : 2026-08-26 16:57

NVD link : CVE-2026-72812

Mitre link : CVE-2026-72812

CVE.ORG link : CVE-2026-72812

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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