FKIE_CVE-2025-66454

Vulnerability from fkie_nvd - Published: 2025-12-02 19:15 - Updated: 2026-10-18 18:10
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Summary
Arcade MCP allows you to to create, deploy, and share MCP Servers. Prior to 1.5.4, the arcade-mcp HTTP server uses a hardcoded default worker secret ("dev") that is never validated or overridden during normal server startup. As a result, any unauthenticated attacker who knows this default key can forge valid JWTs and fully bypass the FastAPI authentication layer. This grants remote access to all worker endpoints—including tool enumeration and tool invocation—without credentials. This vulnerability is fixed in 1.5.4.
References
security-advisories@github.comhttps://github.com/ArcadeAI/arcade-mcp/commit/44660d18ceb220600401303df860a31ca766c817
security-advisories@github.comhttps://github.com/ArcadeAI/arcade-mcp/pull/691
security-advisories@github.comhttps://github.com/ArcadeAI/arcade-mcp/security/advisories/GHSA-g2jx-37x6-6438
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "arcade-mcp",
          "vendor": "ArcadeAI",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.5.4"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Arcade MCP allows you to to create, deploy, and share MCP Servers. Prior to 1.5.4, the arcade-mcp HTTP server uses a hardcoded default worker secret (\"dev\") that is never validated or overridden during normal server startup. As a result, any unauthenticated attacker who knows this default key can forge valid JWTs and fully bypass the FastAPI authentication layer. This grants remote access to all worker endpoints\u2014including tool enumeration and tool invocation\u2014without credentials. This vulnerability is fixed in 1.5.4."
    },
    {
      "lang": "es",
      "value": "Arcade MCP permite crear, desplegar y compartir servidores MCP. Versiones anteriores a 1.5.4, el servidor HTTP arcade-mcp utiliza un secreto de trabajador predeterminado codificado (\u201cdev\u201d) que nunca se valida ni se sobrescribe durante el inicio normal del servidor. Como resultado, cualquier atacante no autenticado que conozca esta clave predeterminada puede falsificar JWT v\u00e1lidos y eludir completamente la capa de autenticaci\u00f3n de FastAPI. Esto otorga acceso remoto a todos los endpoints de trabajador -incluyendo la enumeraci\u00f3n e invocaci\u00f3n de herramientas- sin credenciales. Esta vulnerabilidad se ha corregido en la versi\u00f3n 1.5.4."
    }
  ],
  "id": "CVE-2025-66454",
  "lastModified": "2026-10-18T18:10:00.100",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-66454",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-12-02T19:28:19.190064Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-12-02T19:15:52.683",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ArcadeAI/arcade-mcp/commit/44660d18ceb220600401303df860a31ca766c817"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ArcadeAI/arcade-mcp/pull/691"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ArcadeAI/arcade-mcp/security/advisories/GHSA-g2jx-37x6-6438"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-321"
        },
        {
          "lang": "en",
          "value": "CWE-798"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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