CVE-2025-59528
Flowise is a drag & drop user interface to build a customized large language model flow. In version 3.0.5, Flowise is vulnerable to remote code execution. The CustomMCP node allows users to input configuration settings for connecting to an external MCP server. This node parses the user-provided mcpServerConfig string to build the MCP server configuration. However, during this process, it executes JavaScript code without any security validation.
Leer descripción completaMostrar menos
Specifically, inside the convertToValidJSONString function, user input is directly passed to the Function() constructor, which evaluates and executes the input as JavaScript code. Since this runs with full Node.js runtime privileges, it can access dangerous modules such as child_process and fs. This issue has been patched in version 3.0.6.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- Puntuación base: 10
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 86%
- Percentil entre todas las CVEs puntuadas: 100
- Fecha de la puntuación: 1/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access95 % - Impacto principal
T1059Command and Scripting Interpreterexecution95 % - Impacto secundario
T1565Data Manipulationimpact70 %
Vulnerabilidad RCE en nodo CustomMCP de Flowise 3.0.5: entrada del usuario se evalúa directamente con Function() sin validación, ejecutando JavaScript arbitrario con privilegios de Node.js (CWE-94: improper control of generation of code). AV:N/PR:N permite explotación remota sin autenticación.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-94
Referencias
- https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L132
- https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L220
- https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L262-L270
- https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/controllers/nodes/index.ts#L57-L78
- https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/routes/node-load-methods/index.ts#L5
- https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/services/nodes/index.ts#L91-L94
- https://github.com/FlowiseAI/Flowise/releases/tag/flowise%403.0.6
- https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-3gcm-f6qx-ff7p
JSON original (NVD)
Mostrar
{
"id": "CVE-2025-59528",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2025-59528",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2025-09-22T20:23:40.363660Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 10,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "FlowiseAI",
"product": "Flowise",
"versions": [
{
"status": "affected",
"version": "= 3.0.5"
}
]
}
]
}
],
"published": "2025-09-22T20:15:39.530",
"references": [
{
"url": "https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L132",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L220",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L262-L270",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/controllers/nodes/index.ts#L57-L78",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/routes/node-load-methods/index.ts#L5",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/services/nodes/index.ts#L91-L94",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/releases/tag/flowise%403.0.6",
"tags": [
"Release Notes"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-3gcm-f6qx-ff7p",
"tags": [
"Exploit",
"Vendor Advisory"
],
"source": "security-advisories@github.com"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-94"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Flowise is a drag & drop user interface to build a customized large language model flow. In version 3.0.5, Flowise is vulnerable to remote code execution. The CustomMCP node allows users to input configuration settings for connecting to an external MCP server. This node parses the user-provided mcpServerConfig string to build the MCP server configuration. However, during this process, it executes JavaScript code without any security validation. Specifically, inside the convertToValidJSONString function, user input is directly passed to the Function() constructor, which evaluates and executes the input as JavaScript code. Since this runs with full Node.js runtime privileges, it can access dangerous modules such as child_process and fs. This issue has been patched in version 3.0.6."
}
],
"lastModified": "2026-06-17T09:46:20.590",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:flowiseai:flowise:3.0.5:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "D5D151AD-7484-4BE3-B42F-7D0279B5E886"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}