CVE-2021-34697

{
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              "technicalImpact": "partial"
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          "timestamp": "2024-11-07T21:54:15.131395Z"
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          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "NONE"
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        "impactScore": 2.9,
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        "exploitabilityScore": 10,
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        "exploitabilityScore": 3.9
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          "product": "Cisco IOS XE Software",
          "versions": [
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  "published": "2021-09-23T03:15:16.107",
  "references": [
    {
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-zbfw-tguGuYq",
      "tags": [
        "Vendor Advisory"
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      "source": "psirt@cisco.com"
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    {
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
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      "description": [
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          "lang": "en",
          "value": "CWE-665"
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  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the Protection Against Distributed Denial of Service Attacks feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct denial of service (DoS) attacks to or through the affected device. This vulnerability is due to incorrect programming of the half-opened connections limit, TCP SYN flood limit, or TCP SYN cookie features when the features are configured in vulnerable releases of Cisco IOS XE Software. An attacker could exploit this vulnerability by attempting to flood traffic to or through the affected device. A successful exploit could allow the attacker to initiate a DoS attack to or through an affected device."
    },
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      "lang": "es",
      "value": "Una vulnerabilidad en la funcionalidad Protection Against Distributed Denial of Service Attacks de Cisco IOS XE Software podría permitir a un atacante remoto no autenticado realizar ataques de denegación de servicio (DoS) al dispositivo afectado o mediante él. Esta vulnerabilidad es debido a una programación incorrecta del límite de conexiones semiabiertas, del límite de inundación TCP SYN o de la cookie TCP SYN cuando las funciones están configuradas en versiones vulnerables de Cisco IOS XE Software. Un atacante podría explotar esta vulnerabilidad al intentar inundar el tráfico hacia o mediante el dispositivo afectado. Una explotación con éxito podría permitir al atacante iniciar un ataque de DoS hacia o mediante un dispositivo afectado"
    }
  ],
  "lastModified": "2026-06-17T03:56:22.270",
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  "sourceIdentifier": "psirt@cisco.com"
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