CVE-2026-66395
Full vulnerability record from the local CVENow database.
Description
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
CRITICAL
CVSS score
9.4
(v4.0)
Vulnerability status
Deferred
Source identifier
Published
2026-07-27 16:18:12.083000
Last modified
2026-10-24 13:10:00.147000
View original CVE JSON
{
"id": "CVE-2026-66395",
"sourceIdentifier": "[email protected]",
"published": "2026-07-27T16:18:12.083",
"lastModified": "2026-10-24T13:10:00.147",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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."
},
{
"lang": "es",
"value": "SiYuan desktop anterior a la v3.7.2 contiene una vulnerabilidad de cross-site scripting reflejado en el gestor readme del plugin bazaar que permite a los atacantes ejecutar código arbitrario mediante la creación de un enlace profundo siyuan:// malicioso. Los atacantes pueden inyectar cargas útiles HTML a través del parámetro de nombre del plugin que se ejecutan con acceso completo a Node.js mediante la renderización de insertAdjacentHTML en un renderizador Electron configurado de forma insegura."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "siyuan-note",
"product": "siyuan",
"defaultStatus": "unaffected",
"packageURL": "pkg:golang/github.com/siyuan-note/siyuan",
"versions": [
{
"version": "0",
"lessThan": "3.7.2",
"versionType": "semver",
"status": "affected"
},
{
"version": "3.7.2",
"versionType": "semver",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"baseScore": 9.4,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"userInteraction": "PASSIVE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"subAvailabilityImpact": "HIGH",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
"baseScore": 9.6,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.8,
"impactScore": 6.0
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-07-27T16:23:27.484277Z",
"id": "CVE-2026-66395",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-79"
}
]
}
],
"references": [
{
"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-6gx2-8gcr-x83f",
"source": "[email protected]"
},
{
"url": "https://www.vulncheck.com/advisories/siyuan-desktop-before-reflected-xss-to-rce-via-siyuan-protocol",
"source": "[email protected]"
},
{
"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-6gx2-8gcr-x83f",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
]
}