CVE-2026-74903: Uncontrolled Resource Consumption in siyuan-note siyuan
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.
AI Analysis
Technical Summary
The vulnerability in SiYuan note-taking software affects versions prior to 3.7.4. The /api/lute/spinBlockDOM endpoint is insufficiently protected, allowing authenticated users with lower privilege roles (RoleEditor or RoleReader) to send arbitrary DOM input for transformation. Because the endpoint uses per-path mutex serialization, large payloads can cause uncontrolled resource consumption, leading to endpoint starvation. This is an access control weakness that can be exploited to degrade service availability.
Potential Impact
Authenticated users with RoleEditor or RoleReader privileges can invoke the vulnerable endpoint with large payloads, causing resource exhaustion and endpoint starvation. This can degrade the availability of the affected service. There is no indication of privilege escalation or data confidentiality impact.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to the vulnerable endpoint to trusted users or roles, or apply network-level controls to limit large payload submissions to the endpoint.
CVE-2026-74903: Uncontrolled Resource Consumption in siyuan-note siyuan
Description
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 v4.0
Score 5.3medium
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in SiYuan note-taking software affects versions prior to 3.7.4. The /api/lute/spinBlockDOM endpoint is insufficiently protected, allowing authenticated users with lower privilege roles (RoleEditor or RoleReader) to send arbitrary DOM input for transformation. Because the endpoint uses per-path mutex serialization, large payloads can cause uncontrolled resource consumption, leading to endpoint starvation. This is an access control weakness that can be exploited to degrade service availability.
Potential Impact
Authenticated users with RoleEditor or RoleReader privileges can invoke the vulnerable endpoint with large payloads, causing resource exhaustion and endpoint starvation. This can degrade the availability of the affected service. There is no indication of privilege escalation or data confidentiality impact.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to the vulnerable endpoint to trusted users or roles, or apply network-level controls to limit large payload submissions to the endpoint.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-08-17T10:48:45.738Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a844363c6e8be03322294a0
Added to database: 08/18/2026, 11:34:59 UTC
Last enriched: 08/18/2026, 12:06:36 UTC
Last updated: 08/18/2026, 16:04:08 UTC
Views: 4
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