{
  "id": "CVE-2021-40523",
  "sourceIdentifier": "cve@mitre.org",
  "published": "2021-09-05T19:15:15.030",
  "lastModified": "2021-09-10T19:50:51.270",
  "vulnStatus": "Analyzed",
  "descriptions": [
    {
      "lang": "en",
      "value": "In Contiki 3.0, Telnet option negotiation is mishandled. During negotiation between a server and a client, the server may fail to give the WILL/WONT or DO/DONT response for DO and WILL commands because of improper handling of exception condition, which leads to property violations and denial of service. Specifically, a server sometimes sends no response, because a fixed buffer space is available for all responses and that space may have been exhausted."
    },
    {
      "lang": "es",
      "value": "En Contiki versi\u00f3n 3.0, la negociaci\u00f3n de opciones de Telnet es manejada inapropiadamente. Durante la negociaci\u00f3n entre un servidor y un cliente, el servidor puede fallar en dar la respuesta WILL/WONT o DO/DONT para los comandos DO y WILL debido a un manejo inapropiado de la condici\u00f3n de excepci\u00f3n, que conlleva a violaciones de las propiedades y a una denegaci\u00f3n del servicio. Espec\u00edficamente, un servidor a veces no env\u00eda ninguna respuesta, porque un espacio de b\u00fafer fijo est\u00e1 disponible para todas las respuestas y ese espacio puede haberse agotado"
    }
  ],
  "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:N/A:H",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH"
        },
        "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:N/A:P",
          "accessVector": "NETWORK",
          "accessComplexity": "LOW",
          "authentication": "NONE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0
        },
        "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": "CWE-754"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:contiki-os:contiki:3.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "DCF3DB31-D1C3-4110-8919-13452E797D81"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/contiki-os/contiki/issues/2686",
      "source": "cve@mitre.org",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ]
    }
  ]
}