FKIE_CVE-2026-20084

Vulnerability from fkie_nvd - Published: 2026-03-25 16:16 - Updated: 2026-03-26 15:13
Severity ?
8.6 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Summary
A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be forwarded between VLANs, resulting in a denial of service (DoS) condition. This vulnerability is due to improper handling of BOOTP packets on Cisco Catalyst 9000 Series Switches. An attacker could exploit this vulnerability by sending BOOTP request packets to an affected device. A successful exploit could allow an attacker to forward BOOTP packets from one VLAN to another, resulting in BOOTP VLAN leakage and potentially leading to high CPU utilization. This makes the device unreachable (either through console or remote management) and unable to forward traffic, resulting in a DoS condition. Note: This vulnerability can be exploited with either unicast or broadcast BOOTP packets. There are workarounds that address this vulnerability.
References
psirt@cisco.comhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bootp-WuBhNBxA
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be forwarded between VLANs, resulting in a denial of service (DoS) condition. \r\n\r This vulnerability is due to improper handling of BOOTP packets on Cisco Catalyst 9000 Series Switches. An attacker could exploit this vulnerability by sending BOOTP request packets to an affected device. A successful exploit could allow an attacker to forward BOOTP packets from one VLAN to another, resulting in BOOTP VLAN leakage and potentially leading to high CPU utilization. This makes the device unreachable (either through console or remote management) and unable to forward traffic, resulting in a DoS condition. \r\n\r Note: This vulnerability can be exploited with either unicast or broadcast BOOTP packets.\r\n\r   There are workarounds that address this vulnerability."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en la caracter\u00edstica de DHCP snooping del software Cisco IOS XE podr\u00eda permitir a un atacante remoto no autenticado causar que los paquetes BOOTP sean reenviados entre VLANs, resultando en una condici\u00f3n de denegaci\u00f3n de servicio (DoS). Esta vulnerabilidad se debe a un manejo inadecuado de los paquetes BOOTP en los switches Cisco Catalyst de la serie 9000. Un atacante podr\u00eda explotar esta vulnerabilidad enviando paquetes de solicitud BOOTP a un dispositivo afectado. Un exploit exitoso podr\u00eda permitir a un atacante reenviar paquetes BOOTP de una VLAN a otra, resultando en una fuga de VLAN BOOTP y potencialmente llevando a una alta utilizaci\u00f3n de la CPU. Esto hace que el dispositivo sea inalcanzable (ya sea a trav\u00e9s de la consola o la gesti\u00f3n remota) e incapaz de reenviar tr\u00e1fico, resultando en una condici\u00f3n de DoS. Nota: Esta vulnerabilidad puede ser explotada con paquetes BOOTP unicast o broadcast. Existen soluciones alternativas que abordan esta vulnerabilidad."
    }
  ],
  "id": "CVE-2026-20084",
  "lastModified": "2026-03-26T15:13:33.940",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.6,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 4.0,
        "source": "psirt@cisco.com",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-03-25T16:16:13.563",
  "references": [
    {
      "source": "psirt@cisco.com",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bootp-WuBhNBxA"
    }
  ],
  "sourceIdentifier": "psirt@cisco.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "psirt@cisco.com",
      "type": "Primary"
    }
  ]
}


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