CVE-2026-54759 Cross-site scripting in siyuan
An attacker can execute arbitrary commands on a victim's machine by injecting malicious iframes into package READMEs viewed in the SiYuan Electron client.
- 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-2026-54759?
CVE-2026-54759 is a high-severity cross-site scripting vulnerability in siyuan-note siyuan, published on 24 Jun 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 is an open-source personal knowledge management system. Prior to 3.7.0, Lute's HTML sanitizer does not remove <iframe> elements. Combined with the SiYuan Electron client's permissive security configuration, an attacker can include a malicious <iframe> in a Bazaar package README that executes arbitrary commands on the victim's machine when the package details are viewed. No package installation is required. This vulnerability is fixed in 3.7.0.
Weakness: CWE-79
Which versions are affected by CVE-2026-54759?
How do I fix CVE-2026-54759?
No fix has been published for CVE-2026-54759 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-2026-54759 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54759 exists.
Sources
Also known as GHSA-r6v5-4c66-f6pw.