{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-103256", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-09-30T10:55:39.869Z", "datePublished": "2026-10-01T10:42:00.751Z", "dateUpdated": "2026-10-01T10:42:00.751Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-10-01T10:42:00.751Z"}, "datePublic": "2026-09-16T00:00:00.000Z", "title": "n8n before 2.39.6 and 2.40.x before 2.40.1 Credentials Leak via preAuthentication Hook", "descriptions": [{"lang": "en", "value": "n8n versions before 2.39.6 and 2.40.0 before 2.40.1 contain a credentials leak vulnerability in the Wekan and Baserow username-and-password credentials that sends unencrypted passwords to unvalidated hosts. Attackers with credential update permissions can modify the host field to receive account passwords at arbitrary hosts, bypassing domain validation controls."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Insufficiently Protected Credentials", "cweId": "CWE-522", "type": "CWE"}]}], "affected": [{"vendor": "n8n-io", "product": "n8n", "defaultStatus": "unaffected", "packageURL": "pkg:npm/n8n", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "2.39.6"}, {"version": "2.40.0", "status": "affected", "versionType": "semver", "lessThan": "2.40.1"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*", "versionEndExcluding": "2.39.6"}, {"vulnerable": true, "criteria": "cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.40.0", "versionEndExcluding": "2.40.1"}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:L/SA:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "LOW", "subAvailabilityImpact": "NONE", "baseScore": 7.1, "baseSeverity": "HIGH"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "LOW", "availabilityImpact": "NONE", "baseScore": 7.1, "baseSeverity": "HIGH"}}], "references": [{"url": "https://github.com/n8n-io/n8n/security/advisories/GHSA-gx6g-2hm7-c4xf", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-gx6g-2hm7-c4xf)"}, {"name": "VulnCheck Advisory: n8n before 2.39.6 and 2.40.x before 2.40.1 Credentials Leak via preAuthentication Hook", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/n8n-before-2.39.6-and-2.40-x-before-2.40.1-credentials-leak-via-preauthentication-hook"}], "credits": [{"lang": "en", "value": "nlgbao1340", "type": "reporter"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "packageURL": "pkg:npm/n8n", "product": "n8n", "vendor": "n8n-io", "versions": [{"lessThan": "2.39.6", "status": "affected", "version": "0", "versionType": "semver"}, {"lessThan": "2.40.1", "status": "affected", "version": "2.40.0", "versionType": "semver"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "n8n versions before 2.39.6 and 2.40.0 before 2.40.1 contain a credentials leak vulnerability in the Wekan and Baserow username-and-password credentials that sends unencrypted passwords to unvalidated hosts. Attackers with credential update permissions can modify the host field to receive account passwords at arbitrary hosts, bypassing domain validation controls."}], "id": "CVE-2026-103256", "lastModified": "2026-10-01T11:17:20.047", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 4.7, "source": "[email protected]", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 7.1, "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": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "LOW", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/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": "HIGH", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "[email protected]", "type": "Secondary"}]}, "published": "2026-10-01T11:17:19.913", "references": [{"source": "[email protected]", "url": "https://github.com/n8n-io/n8n/security/advisories/GHSA-gx6g-2hm7-c4xf"}, {"source": "[email protected]", "url": "https://www.vulncheck.com/advisories/n8n-before-2.39.6-and-2.40-x-before-2.40.1-credentials-leak-via-preauthentication-hook"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-522"}], "source": "[email protected]", "type": "Primary"}]}

{}

{}