CVE-2026-42235

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Prior to versions 1.123.32, 2.17.4, and 2.18.1, an unauthenticated attacker could register a malicious MCP OAuth client with a crafted client_name. If a victim user authorized the OAuth consent dialog and a second user subsequently revoked that access, a toast notification would render the injected script. Clicking the link would execute arbitrary JavaScript in the victim's authenticated n8n browser session, enabling credential and session token theft, workflow manipulation, or privilege escalation. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1."}, {"lang": "es", "value": "n8n es una plataforma de automatizaci\u00f3n de flujos de trabajo de c\u00f3digo abierto. Antes de las versiones 1.123.32, 2.17.4 y 2.18.1, un atacante no autenticado podr\u00eda registrar un cliente OAuth MCP malicioso con un client_name manipulado. Si un usuario v\u00edctima autorizaba el di\u00e1logo de consentimiento de OAuth y un segundo usuario posteriormente revocaba ese acceso, una notificaci\u00f3n toast renderizar\u00eda el script inyectado. Al hacer clic en el enlace se ejecutar\u00eda JavaScript arbitrario en la sesi\u00f3n autenticada del navegador n8n de la v\u00edctima, lo que permitir\u00eda el robo de credenciales y tokens de sesi\u00f3n, la manipulaci\u00f3n de flujos de trabajo o la escalada de privilegios. Este problema ha sido parcheado en las versiones 1.123.32, 2.17.4 y 2.18.1."}], "id": "CVE-2026-42235", "lastModified": "2026-11-11T23:10:00.263", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.6, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 6.0, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.8, "baseSeverity": "HIGH", "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": "HIGH", "subIntegrityImpact": "HIGH", "userInteraction": "ACTIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:L/SC:H/SI:H/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": "LOW", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-42235", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-05-05T14:39:57.088046Z", "version": "2.0.3"}}]}, "published": "2026-05-04T19:16:06.173", "references": [{"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/n8n-io/n8n/security/advisories/GHSA-537j-gqpc-p7fq"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}, {"lang": "en", "value": "CWE-87"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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