CVE-2021-21002

Estado: ModificadaAlta (7.5)—

In Phoenix Contact FL COMSERVER UNI in versions < 2.40 a invalid Modbus exception response can lead to a temporary denial of service.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.96%
Percentil entre todas las CVEs puntuadas: 60
Fecha de la puntuación: 7/10/2026

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).

Tecnologías afectadas (2)

Phoenixcontact — FL Comserver UNI 232/422/485-t Firmware Phoenixcontact — FL Comserver UNI 232/422/485 Firmware

CWE

CWE-772

Referencias

JSON original (NVD)

Mostrar

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  "id": "CVE-2021-21002",
  "cveTags": [],
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        "type": "Primary",
        "source": "nvd@nist.gov",
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          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "NONE"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
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    "cvssMetricV31": [
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          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
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  "affected": [
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          "product": "FL COMSERVER",
          "versions": [
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              "status": "affected",
              "version": "UNI 232/422/485 (2313452)",
              "lessThan": "2.40",
              "versionType": "custom"
            },
            {
              "status": "affected",
              "version": "UNI 232/422/485-T (2904817)",
              "lessThan": "2.40",
              "versionType": "custom"
            }
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      ]
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  ],
  "published": "2021-06-25T19:15:08.587",
  "references": [
    {
      "url": "https://cert.vde.com/en-us/advisories/vde-2021-022",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "info@cert.vde.com"
    },
    {
      "url": "https://cert.vde.com/en-us/advisories/vde-2021-022",
      "tags": [
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      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
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      "type": "Secondary",
      "source": "info@cert.vde.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-772"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In Phoenix Contact FL COMSERVER UNI in versions < 2.40 a invalid Modbus exception response can lead to a temporary denial of service."
    },
    {
      "lang": "es",
      "value": "En Phoenix Contact FL COMSERVER UNI en versiones anteriores a 2.40, una respuesta de excepción Modbus no válida puede conllevar a una denegación de servicio temporal"
    }
  ],
  "lastModified": "2026-06-17T03:34:38.333",
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  "sourceIdentifier": "info@cert.vde.com"
}