CVE-2026-66396

SiYuan before v3.7.2 fails to escape the title-img Individual Attribute List value when rendering Gallery and Kanban cover images, allowing stored cross-site scripting via unescaped style attribute interpolation. Attackers with editor permissions can inject onload handlers that execute arbitrary code in the Electron renderer with full Node.js access when victims open affected documents.

CVSS v3 8.4 HIGH

8.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.7 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5rxg-wh59-mg34
https://www.vulncheck.com/advisories/siyuan-before-stored-xss-to-rce-via-title-img-ial
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5rxg-wh59-mg34

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 16:18

Updated : 2026-09-17 18:17

NVD link : CVE-2026-66396

Mitre link : CVE-2026-66396

CVE.ORG link : CVE-2026-66396

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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