CVE-2026-66396
Full vulnerability record from the local CVENow database.
Description
SiYuan before v3.7.2 fails to escape the title-img Individual Attribute List value when rendering Gallery and Kanban cover images, allowing stored cross-site scripting via unescaped style attribute interpolation. Attackers with editor permissions can inject onload handlers that execute arbitrary code in the Electron renderer with full Node.js access when victims open affected documents.
Severity
CRITICAL
CVSS score
9.3
(v4.0)
Vulnerability status
Deferred
Source identifier
Published
2026-07-27 16:18:12.220000
Last modified
2026-10-24 13:10:00.147000
View original CVE JSON
{
"id": "CVE-2026-66396",
"sourceIdentifier": "[email protected]",
"published": "2026-07-27T16:18:12.220",
"lastModified": "2026-10-24T13:10:00.147",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "SiYuan before v3.7.2 fails to escape the title-img Individual Attribute List value when rendering Gallery and Kanban cover images, allowing stored cross-site scripting via unescaped style attribute interpolation. Attackers with editor permissions can inject onload handlers that execute arbitrary code in the Electron renderer with full Node.js access when victims open affected documents."
},
{
"lang": "es",
"value": "SiYuan anterior a la v3.7.2 no logra escapar el valor de la lista de atributos individuales ’title-img’ al renderizar imágenes de portada de Galería y Kanban, lo que permite cross-site scripting almacenado a través de la interpolación de atributos de estilo sin escapar. Atacantes con permisos de editor pueden inyectar manejadores ’onload’ que ejecutan código arbitrario en el renderizador de Electron con acceso completo a Node.js cuando las víctimas abren documentos afectados."
}
],
"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:H/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": 9.3,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "HIGH",
"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:H/UI:R/S:C/C:H/I:H/A:H",
"baseScore": 8.4,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "HIGH",
"userInteraction": "REQUIRED",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.7,
"impactScore": 6.0
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-07-27T17:27:38.513794Z",
"id": "CVE-2026-66396",
"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-5rxg-wh59-mg34",
"source": "[email protected]"
},
{
"url": "https://www.vulncheck.com/advisories/siyuan-before-stored-xss-to-rce-via-title-img-ial",
"source": "[email protected]"
},
{
"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5rxg-wh59-mg34",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
]
}