CVE-2026-41421: SiYuan Desktop Notification XSS Leads to Electron RCE
SiYuan is an open-source personal knowledge management system. Prior to 3.6.5, SiYuan desktop renders notification messages as raw HTML inside an Electron renderer. The notification route POST /api/notification/pushMsg accepts a user-controlled msg value, forwards it through the backend broadcast layer, and the frontend inserts it into the DOM with insertAdjacentHTML(...) at message.ts. On desktop builds, this is not limited to ordinary XSS. Electron windows are created with nodeIntegration: true, contextIsolation: false, and webSecurity: false at main.js. As a result, JavaScript executed from the notification sink can directly access Node APIs and escalate to desktop code execution. This vulnerability is fixed in 3.6.5.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-41421?
CVE-2026-41421 is considered a high-severity vulnerability that can lead to remote code execution due to improper handling of HTML in notifications.
How do I fix CVE-2026-41421?
To fix CVE-2026-41421, upgrade SiYuan Desktop to version 3.6.5 or later.
What type of vulnerability is CVE-2026-41421?
CVE-2026-41421 is categorized as a cross-site scripting (XSS) vulnerability that can lead to remote code execution.
Who is affected by CVE-2026-41421?
Users of SiYuan Desktop prior to version 3.6.5 are affected by CVE-2026-41421.
What can be exploited through CVE-2026-41421?
CVE-2026-41421 can be exploited by an attacker to execute arbitrary code on a vulnerable system through manipulated notification messages.