CVE-2026-33066 MEDIUM

CVE-2026-33066: SiYuan has Stored XSS to RCE via Unsanitized Bazaar README Rendering

Vendor Siyuan-Note
Product siyuan
Weakness CWE-79 · XSS
Published March 20, 2026
Last update March 20, 2026

CVSS base score

5.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

March 20, 2026 CVE published
March 20, 2026 Record updated

Related vulnerabilities

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