CVE-2026-74903

SiYuan before v3.7.4 contains an insufficient access control vulnerability in the /api/lute/spinBlockDOM endpoint, which is guarded only by CheckAuth middleware instead of CheckAdminRole like its sibling endpoint. Authenticated users with RoleEditor or RoleReader roles can invoke the endpoint to transform arbitrary DOM input, and large payloads cause endpoint starvation through per-path mutex serialization.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3j8q-5c8c-grwm
https://www.vulncheck.com/advisories/siyuan-before-insufficient-access-control-via-spinblockdom
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3j8q-5c8c-grwm

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-18 12:19

Updated : 2026-08-26 17:04

NVD link : CVE-2026-74903

Mitre link : CVE-2026-74903

CVE.ORG link : CVE-2026-74903

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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