CVE-2026-65606 SiYuan before v3.7.2 Cross-Site Scripting to RCE
Attackers can execute arbitrary OS commands via XSS in the siyuan:// protocol handler due to unescaped innerHTML and Node integration.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-65606?
CVE-2026-65606 is a critical cross-site scripting vulnerability in siyuan-note siyuan, published on 23 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
SiYuan before v3.7.2 contains a cross-site scripting vulnerability in the siyuan:// protocol handler. When a siyuan://plugins/<name> link references a name that is not an installed plugin, the application opens a custom tab and inserts the link's icon parameter into the tab header via innerHTML without escaping it (app/src/layout/Tab.ts), allowing injection of an <img onerror=...> element. Because the SiYuan Desktop renderer runs with nodeIntegration:true, the injected JavaScript can access Node's require and call require('child_process').execSync(...), escalating the cross-site scripting into arbitrary operating-system command execution.
Weakness: CWE-79
Which versions are affected by CVE-2026-65606?
How do I fix CVE-2026-65606?
No fix has been published for CVE-2026-65606 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-2026-65606 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-65606 exists.
Sources
Also known as GHSA-3vr3-hq5c-q2w9, GHSA-wp64-x7qh-h728.