CVE-2026-34585 PUBLISHED

SiYuan: Stored XSS in imported .sy.zip content leads to arbitrary command execution

Assigner: GitHub_M
Reserved: 30.03.2026 Published: 31.03.2026 Updated: 01.04.2026

SiYuan is a personal knowledge management system. Prior to version 3.6.2, a vulnerability allows crafted block attribute values to bypass server-side attribute escaping when an HTML entity is mixed with raw special characters. An attacker can embed a malicious IAL value inside a .sy document, package it as a .sy.zip, and have the victim import it through the normal Import -> SiYuan .sy.zip workflow. Once the note is opened, the malicious attribute breaks out of its original HTML context and injects an event handler, resulting in stored XSS. In the Electron desktop client, this XSS reaches remote code execution because injected JavaScript runs with access to Node/Electron APIs. This issue has been patched in version 3.6.2.

Metrics

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CVSS Score: 8.6

Product Status

Vendor siyuan-note
Product siyuan
Versions
  • Version < 3.6.2 is affected

References

Problem Types

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE
  • CWE-94: Improper Control of Generation of Code ('Code Injection') CWE