FKIE_CVE-2026-20004

Vulnerability from fkie_nvd - Published: 2026-03-25 16:16 - Updated: 2026-03-26 15:13
Severity ?
7.4 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Summary
A vulnerability in the TLS library of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust the available memory of an affected device. This vulnerability is due to improper management of memory resources during TLS connection setup. An attacker could exploit this vulnerability by repeatedly triggering the conditions that cause the memory increase. This could be done in a variety of ways, such as by repeatedly attempting Extensible Authentication Protocol (EAP) authentication when local EAP is enabled on an affected device or by using a machine-in-the-middle attack and resetting TLS connections between the affected device and other devices. A successful exploit could allow the attacker to exhaust the available memory on an affected device, resulting in an unexpected reload and a denial of service (DoS) condition.
References
psirt@cisco.comhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-tls-dos-TVgLDEZL
Impacted products
Vendor Product Version
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{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the TLS library of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust the available memory of an affected device.\r\n\r This vulnerability is due to improper management of memory resources during TLS connection setup. An attacker could exploit this vulnerability by repeatedly triggering the conditions that cause the memory increase. This could be done in a variety of ways, such as by repeatedly attempting Extensible Authentication Protocol (EAP) authentication when local EAP is enabled on an affected device or by using a machine-in-the-middle attack and resetting TLS connections between the affected device and other devices. A successful exploit could allow the attacker to exhaust the available memory on an affected device, resulting in an unexpected reload and a denial of service (DoS) condition."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en la biblioteca TLS del software Cisco IOS XE podr\u00eda permitir a un atacante adyacente no autenticado agotar la memoria disponible de un dispositivo afectado. Esta vulnerabilidad se debe a una gesti\u00f3n inadecuada de los recursos de memoria durante la configuraci\u00f3n de la conexi\u00f3n TLS. Un atacante podr\u00eda explotar esta vulnerabilidad desencadenando repetidamente las condiciones que causan el aumento de memoria. Esto podr\u00eda hacerse de varias maneras, como intentando repetidamente la autenticaci\u00f3n del Protocolo de Autenticaci\u00f3n Extensible (EAP) cuando el EAP local est\u00e1 habilitado en un dispositivo afectado o utilizando un ataque de intermediario y restableciendo las conexiones TLS entre el dispositivo afectado y otros dispositivos. Un exploit exitoso podr\u00eda permitir al atacante agotar la memoria disponible en un dispositivo afectado, lo que resultar\u00eda en una recarga inesperada y una condici\u00f3n de denegaci\u00f3n de servicio (DoS)."
    }
  ],
  "id": "CVE-2026-20004",
  "lastModified": "2026-03-26T15:13:33.940",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 4.0,
        "source": "psirt@cisco.com",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-03-25T16:16:10.520",
  "references": [
    {
      "source": "psirt@cisco.com",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-tls-dos-TVgLDEZL"
    }
  ],
  "sourceIdentifier": "psirt@cisco.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-771"
        }
      ],
      "source": "psirt@cisco.com",
      "type": "Primary"
    }
  ]
}


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