CVE-2026-34585

Severity CVSS v4.0:

Pending analysis

Type:

CWE-79 Cross-Site Scripting (XSS)

Publication date:

31/03/2026

Last modified:

03/04/2026

Description

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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.60 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): High