{
  "id": "CVE-2020-27632",
  "sourceIdentifier": "cve@mitre.org",
  "published": "2021-03-10T18:15:12.797",
  "lastModified": "2024-11-21T05:21:32.823",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In SIMATIC MV400 family versions prior to v7.0.6, the ISN generator is initialized with a constant value and has constant increments. An attacker could predict and hijack TCP sessions."
    },
    {
      "lang": "es",
      "value": "En la familia SIMATIC MV400 versiones anteriores a la v7.0.6, el generador ISN es inicializado con un valor constante y presenta incrementos constantes. Un atacante podr\u00eda predecir y secuestrar sesiones de TCP"
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "nvd@nist.gov",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "cvssMetricV2": [
      {
        "source": "nvd@nist.gov",
        "type": "Primary",
        "cvssData": {
          "version": "2.0",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:P/A:N",
          "baseScore": 5.0,
          "accessVector": "NETWORK",
          "accessComplexity": "LOW",
          "authentication": "NONE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "availabilityImpact": "NONE"
        },
        "baseSeverity": "MEDIUM",
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "acInsufInfo": false,
        "obtainAllPrivilege": false,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ]
  },
  "weaknesses": [
    {
      "source": "nvd@nist.gov",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    }
  ],
  "configurations": [
    {
      "operator": "AND",
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:siemens:simatic_mv420_firmware:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "7.0.6",
              "matchCriteriaId": "AA65BD0C-3249-4AB6-A066-C55ADC06EDB7"
            }
          ]
        },
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": false,
              "criteria": "cpe:2.3:h:siemens:simatic_mv420:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "79B15C1B-2510-434B-A589-5903CA0C00EE"
            }
          ]
        }
      ]
    },
    {
      "operator": "AND",
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:siemens:simatic_mv440_firmware:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "7.0.6",
              "matchCriteriaId": "2FCC833E-AA77-471E-87CA-40B5E354163F"
            }
          ]
        },
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": false,
              "criteria": "cpe:2.3:h:siemens:simatic_mv440:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "6408042E-7E06-4AED-9853-29B176EDFE9F"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-599268.pdf",
      "source": "cve@mitre.org",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01",
      "source": "cve@mitre.org"
    },
    {
      "url": "https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/",
      "source": "cve@mitre.org"
    },
    {
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-599268.pdf",
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ]
}