CVE-2026-33066

SiYuan is a personal knowledge management system. In versions 3.6.0 and below, the backend renderREADME function uses lute.New() without calling SetSanitize(true), allowing raw HTML embedded in Markdown to pass through unmodified. The frontend then assigns the rendered HTML to innerHTML without any additional sanitization. A malicious package author can embed arbitrary JavaScript in their README that executes when a user clicks to view the package details. Because SiYuan's Electron configuration enables nodeIntegration: true with contextIsolation: false, this XSS escalates directly to full Remote Code Execution. The issue was patched in version 3.6.1.

CVSS v3 9.0 CRITICAL

9.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/commit/b382f50e1880ed996364509de5a10a72d7409428	Patch
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4663-4mpg-879v	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-20 09:16

Updated : 2026-03-23 15:31

NVD link : CVE-2026-33066

Mitre link : CVE-2026-33066

CVE.ORG link : CVE-2026-33066

JSON object : View

Products Affected

b3log

siyuan

CWE

CWE-79

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

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