CVE-2021-25663

Estado: ModificadaAlta (8.7)—

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (All versions including affected IPv6 stack). The function that processes IPv6 headers does not check the lengths of extension header options, allowing attackers to put this function into an infinite loop with crafted length values.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 8.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 1.88%
Percentil entre todas las CVEs puntuadas: 79
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 (4)

Siemens — Capital Vstar Siemens — Nucleus NET Siemens — Nucleus Readystart Siemens — Nucleus Source Code

CWE

CWE-835
CWE-835

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2021-25663",
  "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
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "productcert@siemens.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "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"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      },
      {
        "type": "Secondary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "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"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
    ],
    "cvssMetricV40": [
      {
        "type": "Secondary",
        "source": "productcert@siemens.com",
        "cvssData": {
          "Safety": "NOT_DEFINED",
          "version": "4.0",
          "Recovery": "NOT_DEFINED",
          "baseScore": 8.7,
          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "exploitMaturity": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "subIntegrityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "vulnAvailabilityImpact": "HIGH",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
        }
      }
    ]
  },
  "affected": [
    {
      "source": "productcert@siemens.com",
      "affectedData": [
        {
          "vendor": "Siemens",
          "product": "Capital Embedded AR Classic 431-422",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "*",
              "versionType": "custom"
            }
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Siemens",
          "product": "Capital Embedded AR Classic R20-11",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "V2303",
              "versionType": "custom"
            }
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Siemens",
          "product": "Nucleus NET",
          "versions": [
            {
              "status": "affected",
              "version": "All versions"
            }
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Siemens",
          "product": "Nucleus ReadyStart V3",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "V2017.02.4",
              "versionType": "custom"
            }
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Siemens",
          "product": "Nucleus ReadyStart V4",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "V4.1.0",
              "versionType": "custom"
            }
          ],
          "defaultStatus": "unknown"
        },
        {
          "vendor": "Siemens",
          "product": "Nucleus Source Code",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "*",
              "versionType": "custom"
            }
          ],
          "defaultStatus": "unknown"
        }
      ]
    }
  ],
  "published": "2021-04-22T21:15:09.957",
  "references": [
    {
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-248289.html",
      "source": "productcert@siemens.com"
    },
    {
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-248289.pdf",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "productcert@siemens.com"
    },
    {
      "url": "https://us-cert.cisa.gov/ics/advisories/icsa-21-103-05",
      "tags": [
        "Third Party Advisory",
        "US Government Resource"
      ],
      "source": "productcert@siemens.com"
    },
    {
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-248289.html",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-248289.pdf",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://us-cert.cisa.gov/ics/advisories/icsa-21-103-05",
      "tags": [
        "Third Party Advisory",
        "US Government Resource"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "productcert@siemens.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-835"
        }
      ]
    },
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-835"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (All versions including affected IPv6 stack). The function that processes IPv6 headers does not check the lengths of extension header options, allowing attackers to put this function into an infinite loop with crafted length values."
    },
    {
      "lang": "es",
      "value": "Se ha identificado una vulnerabilidad en Capital VSTAR (Versiones que incluyen la pila IPv6 afectada), Nucleus NET (Todas las versiones), Nucleus ReadyStart V3 (Todas las versiones anteriores a V2017.02.4), Nucleus ReadyStart V4 (Todas las versiones anteriores a V4.1.0), Nucleus Source Code (Versiones que incluyen la pila IPv6 afectada). La función que procesa las cabeceras de IPv6 no comprueba las longitudes de las opciones de las cabeceras de extensión, lo que permite a los atacantes poner esta función en un bucle infinito con valores de longitud manipulados"
    }
  ],
  "lastModified": "2026-06-17T03:42:18.710",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:siemens:capital_vstar:-:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "EEBF34F7-F37A-4FD1-957E-B2E5DEE7A778"
            },
            {
              "criteria": "cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7A987CFB-4A41-4F82-8C7F-31DE8F0650DE"
            },
            {
              "criteria": "cpe:2.3:a:siemens:nucleus_readystart:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7A5FA7B8-2F94-4762-ADBF-71C0F37231AB",
              "versionEndExcluding": "4.1.0"
            },
            {
              "criteria": "cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "53A38C64-612A-4BC5-83D5-D3FA1C90E0F7"
            }
          ],
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:siemens:nucleus_readystart:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F768DEFE-CE6F-4210-B728-9C4CA2AF03FE",
              "versionEndExcluding": "2017.02.4"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "productcert@siemens.com"
}