CVE-2026-41148

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That value then flows unsanitized through addStyleClass() into createCssStyles() and is assigned to style.innerHTML, so a closing brace (}) in the value terminates the generated CSS selector and turns everything after it into a new CSS rule on the page. This enables page defacement, user tracking via url() callbacks, and DOM attribute exfiltration. This issue has been fixed in versions 10.9.6 and 11.15.0. If developers are unable to immediately upgrade, they can work around this issue by setting \"securityLevel\": \"sandbox\", which prevents the issue by rendering the mermaid diagram in a sandboxed <iframe>."}, {"lang": "es", "value": "Mermaid es una herramienta de JavaScript que utiliza texto inspirado en Markdown para crear y modificar diagramas y gr\u00e1ficos. Las versiones 10.9.5 y anteriores, adem\u00e1s de la 11.0.0-alpha.1 hasta la 11.12.0, son vulnerables a la inyecci\u00f3n de CSS debido a una sanitizaci\u00f3n inadecuada. El diagrama de estados (y cualquier otro tipo de diagrama que enruta cadenas de estilo controladas por el usuario a trav\u00e9s del analizador createCssStyles) captura valores de classDef utilizando una expresi\u00f3n regular no restringida que coincide con todo hasta un salto de l\u00ednea. Ese valor luego fluye sin sanitizar a trav\u00e9s de addStyleClass() hacia createCssStyles() y se asigna a style.innerHTML, por lo que una llave de cierre (}) en el valor termina el selector CSS generado y convierte todo lo que le sigue en una nueva regla CSS en la p\u00e1gina. Esto permite la desfiguraci\u00f3n de p\u00e1ginas, el seguimiento de usuarios a trav\u00e9s de devoluciones de llamada url() y la exfiltraci\u00f3n de atributos DOM. Este problema ha sido solucionado en las versiones 10.9.6 y 11.15.0. Si los desarrolladores no pueden actualizar de inmediato, pueden solucionar este problema estableciendo 'securityLevel': 'sandbox', lo que evita el problema al renderizar el diagrama de mermaid en un <iframe> en sandbox."}], "id": "CVE-2026-41148", "lastModified": "2026-07-23T11:10:00.120", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 5.3, "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": "LOW", "subConfidentialityImpact": "LOW", "subIntegrityImpact": "LOW", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L/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": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-41148", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-27T13:25:29.202814Z", "version": "2.0.3"}}]}, "published": "2026-05-22T23:16:53.593", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/mermaid-js/mermaid/commit/8fead23c59166b7bab6a39eac81acebee2859102"}, {"source": "security-advisories@github.com", "url": "https://github.com/mermaid-js/mermaid/commit/e9b0f34d8d82a6260077764ee45e1d7d90957a0f"}, {"source": "security-advisories@github.com", "url": "https://github.com/mermaid-js/mermaid/releases/tag/mermaid%4011.15.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/mermaid-js/mermaid/releases/tag/v10.9.6"}, {"source": "security-advisories@github.com", "url": "https://github.com/mermaid-js/mermaid/security/advisories/GHSA-xcj9-5m2h-648r"}, {"source": "security-advisories@github.com", "url": "https://mermaid.js.org/config/schema-docs/config.html#securitylevel"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-94"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

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