CVE-2026-58057
Full vulnerability record from the local CVENow database.
Description
Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.
Severity
LOW
CVSS score
2.3
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-06-28 02:16:32.990000
Last modified
2026-10-25 17:10:00.197000
View original CVE JSON
{
"id": "CVE-2026-58057",
"sourceIdentifier": "[email protected]",
"published": "2026-06-28T02:16:32.990",
"lastModified": "2026-10-25T17:10:00.197",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context."
},
{
"lang": "es",
"value": "Flowise antes de la versión 3.1.3 valida las variables de entorno stdio de Custom MCP contra una lista de denegación utilizando una comparación que distingue entre mayúsculas y minúsculas, por lo que en Windows, donde los nombres de las variables de entorno no distinguen entre mayúsculas y minúsculas, proporcionar ’node_options’ elude la entrada NODE_OPTIONS de la lista de denegación. Un usuario autenticado que puede configurar un nodo Custom MCP puede así inyectar NODE_OPTIONS --require y ejecutar código arbitrario en el contexto del servidor Flowise."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Flowise",
"product": "Flowise",
"defaultStatus": "unaffected",
"packageURL": "pkg:npm/flowise",
"versions": [
{
"version": "0",
"lessThan": "3.1.3",
"versionType": "semver",
"status": "affected"
},
{
"version": "3.1.3",
"versionType": "semver",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/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": 2.3,
"baseSeverity": "LOW",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "LOW",
"vulnIntegrityImpact": "LOW",
"vulnAvailabilityImpact": "LOW",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"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": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L",
"baseScore": 5.0,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"availabilityImpact": "LOW"
},
"exploitabilityScore": 1.6,
"impactScore": 3.4
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-06-29T12:23:43.023783Z",
"id": "CVE-2026-58057",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-178"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*",
"versionEndExcluding": "3.1.3",
"matchCriteriaId": "8C8B3FC2-6070-4400-9690-FCBE0C5C1D37"
}
]
}
]
}
],
"references": [
{
"url": "https://github.com/FlowiseAI/Flowise/pull/6471",
"source": "[email protected]",
"tags": [
"Issue Tracking",
"Patch"
]
},
{
"url": "https://github.com/bikini/exploitarium/tree/main/flowise-mcp-env-case-bypass-poc",
"source": "[email protected]",
"tags": [
"Exploit",
"Third Party Advisory"
]
},
{
"url": "https://www.vulncheck.com/advisories/flowise-custom-mcp-environment-variable-denylist-bypass-via-case-sensitivity",
"source": "[email protected]",
"tags": [
"Exploit",
"Patch",
"Third Party Advisory"
]
}
]
}