Vulnary
← back to the feed
Critical· 9.4

CVE-2026-66395

SiYuan desktop versions prior to 3.7.2 contain a reflected cross‑site scripting flaw in the bazaar plugin’s readme handler. By sending a specially crafted siyuan:// deep link, an attacker can inject HTML that runs with full Node.js privileges. This allows the attacker to execute arbitrary code on the victim’s machine.

publishedJul 27, 2026
last modifiedJul 28, 2026
sourcesNVD
severity · cvss
9.4
critical · how bad it is
exploitation · epss
<1%
25th percentile · chance of exploitation in 30 days
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
auto-deletes from the system
counting…on Sep 10, 2026

No official fix yet. If none appears within 45 days of first tracking, this entry is removed automatically.

01

Who is affected

Users of SiYuan desktop before version 3.7.2 who have the bazaar plugin enabled.

02

Real-world impact

An attacker can run any code on the victim’s computer, potentially stealing data, installing malware, or taking full control of the system.

03

Why this severity

The CVSS score of 9.4 reflects the vulnerability’s high impact: it grants attackers full Node.js access (confidentiality, integrity, and availability are all compromised) and requires only a crafted link, making exploitation trivial for a motivated attacker.

04

What to do about it

no official fix yet

No official fix or mitigation is documented in the sources yet. Monitor the vendor advisory and apply the patch as soon as it is released.

No fix documented in sources

05

Timeline

06

How it’s attacked

Attack vectorNetwork (remote)
Attack complexityLow
Attack requirementsNone
Privileges requiredNone
User interactionPassive
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
07

References & advisories

(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
CVE-2026-66395: SiYuan desktop versions prior to 3.7.2 contain a reflected cross‑site · Vulnary