CVE-2026-34585CWE-79CWE-94

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

High · published March 31, 2026

CVSS v3.1
8.6
EPSS
0%
Percentile
28.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.6 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00358 · 28.4th percentile
Weaknesses
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'); CWE-94 · Improper Control of Generation of Code ('Code Injection')
Published
2026-03-31T21:47Z
EPSS history
Timeline
  • 31 MAR 21:47Z
    SiYuan: Stored XSS in imported .sy.zip content leads to arbitrary command execution
    cvelistv5