CVE-2018-4850

Estado: ModificadaAlta (7.5)—

A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions < V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart.

CVSS

Versión: 3.0
Vector: CVSS:3.0/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: 2.42%
Percentil entre todas las CVEs puntuadas: 84
Fecha de la puntuación: 6/10/2026

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)

Siemens — Simatic S7-400 Firmware Siemens — Simatic S7-400h Firmware

CWE

CWE-20
NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2018-4850",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 5,
          "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
      }
    ],
    "cvssMetricV30": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.0",
          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.0/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"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "productcert@siemens.com",
      "affectedData": [
        {
          "vendor": "Siemens AG",
          "product": "SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below, SIMATIC S7-400 (incl. F) CPU hardware version 5.0, SIMATIC S7-400H CPU hardware version 4.5 and below",
          "versions": [
            {
              "status": "affected",
              "version": "SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below : All versions"
            },
            {
              "status": "affected",
              "version": "SIMATIC S7-400 (incl. F) CPU hardware version 5.0 : All firmware versions < V5.2"
            },
            {
              "status": "affected",
              "version": "SIMATIC S7-400H CPU hardware version 4.5 and below : All versions"
            }
          ]
        }
      ]
    }
  ],
  "published": "2018-05-16T17:29:00.387",
  "references": [
    {
      "url": "http://www.securityfocus.com/bid/104217",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ],
      "source": "productcert@siemens.com"
    },
    {
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-914382.pdf",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "productcert@siemens.com"
    },
    {
      "url": "https://www.siemens.com/global/en/home/products/services/cert.html#SecurityPublications",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "productcert@siemens.com"
    },
    {
      "url": "http://www.securityfocus.com/bid/104217",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-914382.pdf",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://www.siemens.com/global/en/home/products/services/cert.html#SecurityPublications",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "productcert@siemens.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        }
      ]
    },
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability has been identified in SIMATIC S7-400 (incl. F) CPU hardware version 4.0 and below (All versions), SIMATIC S7-400 (incl. F) CPU hardware version 5.0 (All firmware versions < V5.2), SIMATIC S7-400H CPU hardware version 4.5 and below (All versions). The affected CPUs improperly validate S7 communication packets which could cause a Denial-of-Service condition of the CPU. The CPU will remain in DEFECT mode until manual restart."
    },
    {
      "lang": "es",
      "value": "Se ha identificado una vulnerabilidad en SIMATIC S7-400 (incl. F) CPU en versiones de hardware 4.0 y anteriores (todas las versiones), SIMATIC S7-400 (incl. F) CPU en versiones de hardware 5.0 (todas las versiones anteriores a la V5.2), SIMATIC S7-400H CPU en versiones de hardware 4.5 y anteriores (todas las versiones). Las CPU afectadas validan incorrectamente los paquetes de comunicación S7 que podrían provocar una condición de denegación de servicio (DoS) en la CPU. La CPU continuará en modo DEFECT hasta que se reinicie manualmente."
    }
  ],
  "lastModified": "2026-06-17T01:59:10.100",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:siemens:simatic_s7-400_firmware:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "3F8B29A7-5912-4815-B1DA-595A980ED365",
              "versionEndIncluding": "4.0"
            }
          ],
          "operator": "OR"
        },
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:h:siemens:simatic_s7-400:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "8F97B67B-4516-4AD9-B33C-7F480EE0DB4D"
            }
          ],
          "operator": "OR"
        }
      ],
      "operator": "AND"
    },
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:siemens:simatic_s7-400_firmware:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "A4C0C1ED-74B7-4E4B-B982-062176B7DA2D",
              "versionEndExcluding": "5.2"
            }
          ],
          "operator": "OR"
        },
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:h:siemens:simatic_s7-400:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "8F97B67B-4516-4AD9-B33C-7F480EE0DB4D"
            }
          ],
          "operator": "OR"
        }
      ],
      "operator": "AND"
    },
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:siemens:simatic_s7-400h_firmware:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F150F79A-3843-4A31-8343-75DAF186030F",
              "versionEndIncluding": "4.5"
            }
          ],
          "operator": "OR"
        },
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:h:siemens:simatic_s7-400h:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "1D1CCAFD-1D34-4893-9B3E-76CAD323179A"
            }
          ],
          "operator": "OR"
        }
      ],
      "operator": "AND"
    }
  ],
  "sourceIdentifier": "productcert@siemens.com"
}