CVE-2026-6827

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Programmatic script/style/Comment nodes could serialize into active markup. Additional hardening fixes address sanitize-pipeline cache mutation and DOM parent/child cycles that could cause infinite loops. Most issues affect advanced or custom configurations rather than the default JustHTML(..., sanitize=True) safe path."}, {"lang": "es", "value": "justhtml anterior a la versi\u00f3n 1.17.0 contiene m\u00faltiples problemas de seguridad en la sanitizaci\u00f3n, serializaci\u00f3n y manejo program\u00e1tico del DOM. Cuando las pol\u00edticas personalizadas preservan espacios de nombres externos (SVG/MathML), contenido peligroso como puntos de integraci\u00f3n HTML (SVG <foreignObject>, MathML <annotation-xml encoding=\u201ctext/html\u201d>) y cargas \u00fatiles de XSS por mutaci\u00f3n con diferencias de analizador podr\u00edan sobrevivir a la sanitizaci\u00f3n y convertirse en HTML activo despu\u00e9s de un nuevo an\u00e1lisis; SVG filter=\u201curl(...)\u201d y <style> preservado podr\u00edan dejar CSS de carga de recursos (@import, background-image:url()). Los nodos program\u00e1ticos de script/style/Comment podr\u00edan serializarse en marcado activo. Correcciones de endurecimiento adicionales abordan la mutaci\u00f3n de la cach\u00e9 de la tuber\u00eda de sanitizaci\u00f3n y los ciclos padre/hijo del DOM que podr\u00edan causar bucles infinitos. La mayor\u00eda de los problemas afectan a configuraciones avanzadas o personalizadas en lugar de la ruta segura predeterminada de JustHTML(..., sanitize=True)."}], "id": "CVE-2026-6827", "lastModified": "2026-10-12T16:10:00.220", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 2.7, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 5.1, "baseSeverity": "MEDIUM", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "LOW", "subIntegrityImpact": "LOW", "userInteraction": "ACTIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-6827", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-08-26T18:05:56.854604Z", "version": "2.0.3"}}]}, "published": "2026-08-23T14:16:53.963", "references": [{"source": "disclosure@vulncheck.com", "url": "https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-vrx2-77f2-ww34"}, {"source": "disclosure@vulncheck.com", "url": "https://www.vulncheck.com/advisories/justhtml-before-multiple-cross-site-scripting-vulnerabilities"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "disclosure@vulncheck.com", "type": "Secondary"}]}

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{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.16.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "1.16.0"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "justhtml", "source": "cna", "vendor": "EmilStenstrom"}, "product": "justhtml", "vendor": "emilstenstrom"}], "created": "2026-08-23T15:45:04.505913+00:00", "updated": "2026-08-23T16:39:42.536963+00:00", "vendors": ["emilstenstrom", "emilstenstrom$PRODUCT$justhtml"]}