Executive brief
SiYuan is a note-taking and knowledge management application that allows users to create databases with customizable select fields. Attackers can inject malicious JavaScript code through the color field of select options, which executes whenever anyone views a database containing the compromised field. Because the vulnerability affects normal database viewing—not just menu interactions—the exploit payload runs automatically when users open the affected database, potentially allowing attackers to steal data, modify content, or take control of the application in desktop clients.
Technical details
The vulnerability is a stored cross-site scripting (XSS) flaw in the attribute-view select option color field. The kernel accepts arbitrary strings for the color field (documented as a palette index 1–14 but never validated on write), and eight frontend render sites interpolate this value directly into style attributes without HTML escaping. An attacker can inject a quotation mark followed by event-handler attributes (e.g., `1);color:red" onmouseover="alert(1)" x="`) to break out of the style attribute and inject JavaScript. The payload executes whenever the select option is rendered—including in table, gallery, kanban, relation views and filter menus. In the desktop client, renderer processes have Node integration enabled (webSecurity: false, nodeIntegration: true), allowing script execution to access Node.js primitives like child_process. The vulnerability is triggered by any path bringing a malicious database to the victim (import, sync, shared workspace, or package distribution). Patches are available in v3.7.4 and later.
Affected products
- SiYuan SiYuan before v3.7.4
Timeline
- 2026-08-15: disclosed
- 2026-08-01: patched: patch released in v3.7.4