CVE-2026-41421 SiYuan Desktop Notification XSS Leads to Electron RCE
Attacker can execute arbitrary code on desktop via XSS in notifications due to insecure Electron configuration.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-41421?
CVE-2026-41421 is a high-severity cross-site scripting vulnerability in siyuan-note siyuan, published on 24 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-41421?
How do I fix CVE-2026-41421?
No fix has been published for CVE-2026-41421 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-41421 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-41421 exists.
Sources
Also known as GHSA-grjj-6f6g-cq8q.