CVE-2026-66394

SiYuan before v3.7.3 contains stored and reflected cross-site scripting vulnerabilities in SVG sanitization that allows authenticated attackers to execute scripts by bypassing the HTML parser-based cleaner. Attackers can hide script tags within desc, style, or noscript elements which the HTML parser treats as raw text but browsers interpret as executable SVG content when served as image/svg+xml, enabling script execution in the application origin.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-99rq-75j6-5j9f
https://www.vulncheck.com/advisories/siyuan-before-stored-and-reflected-xss-via-svg-sanitizer-bypass
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-99rq-75j6-5j9f

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 16:18

Updated : 2026-07-28 16:07

NVD link : CVE-2026-66394

Mitre link : CVE-2026-66394

CVE.ORG link : CVE-2026-66394

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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