CVE-2026-66395

SiYuan desktop before v3.7.2 contains a reflected cross-site scripting vulnerability in the bazaar plugin readme handler that allows attackers to execute arbitrary code by crafting a malicious siyuan:// deep link. Attackers can inject HTML payloads via the plugin name parameter that execute with full Node.js access through insertAdjacentHTML rendering in an insecurely configured Electron renderer.

CVSS v3 9.6 CRITICAL

9.6^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.8 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

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-6gx2-8gcr-x83f
https://www.vulncheck.com/advisories/siyuan-desktop-before-reflected-xss-to-rce-via-siyuan-protocol
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-6gx2-8gcr-x83f

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 16:18

Updated : 2026-09-17 18:17

NVD link : CVE-2026-66395

Mitre link : CVE-2026-66395

CVE.ORG link : CVE-2026-66395

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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