CVE-2026-66395 (GCVE-0-2026-66395)

Vulnerability from cvelistv5 – Published: 2026-07-27 15:43 – Updated: 2026-09-17 17:54
VLAI
Title
SiYuan Desktop before v3.7.2 Reflected XSS to RCE via siyuan Protocol
Summary
SiYuan desktop before v3.7.2 contains a reflected cross-site scripting vulnerability in the bazaar plugin readme handler that allows attackers to execute arbitrary code by crafting a malicious siyuan:// deep link. Attackers can inject HTML payloads via the plugin name parameter that execute with full Node.js access through insertAdjacentHTML rendering in an insecurely configured Electron renderer.
Severity
9.4 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
9.6 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-27 16:23 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 8194 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
siyuan-note siyuan Affected: 0 , < 3.7.2 (semver)
Unaffected: 3.7.2 (semver)
    cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-13 00:00
Credits
hypnguyen1209
Show details on NVD website
To clipboard 

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