CVE-2026-66395 (GCVE-0-2026-66395)
Vulnerability from cvelistv5 – Published: 2026-07-27 15:43 – Updated: 2026-09-17 17:54
VLAI
EPSS
VEX
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
9.6 (Critical)
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
References
2 references
| URL | Tags |
|---|---|
| https://github.com/siyuan-note/siyuan/security/ad… | vendor-advisory |
| https://www.vulncheck.com/advisories/siyuan-deskt… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| siyuan-note | siyuan |
Affected:
0 , < 3.7.2
(semver)
Unaffected: 3.7.2 (semver) cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:* |
Date Public
2026-07-13 00:00
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Nomenclature
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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