FKIE_CVE-2021-43173

Vulnerability from fkie_nvd - Published: 2021-11-09 17:15 - Updated: 2026-06-17 04:10
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Summary
In NLnet Labs Routinator prior to 0.10.2, a validation run can be delayed significantly by an RRDP repository by not answering but slowly drip-feeding bytes to keep the connection alive. This can be used to effectively stall validation. While Routinator has a configurable time-out value for RRDP connections, this time-out was only applied to individual read or write operations rather than the complete request. Thus, if an RRDP repository sends a little bit of data before that time-out expired, it can continuously extend the time it takes for the request to finish. Since validation will only continue once the update of an RRDP repository has concluded, this delay will cause validation to stall, leading to Routinator continuing to serve the old data set or, if in the initial validation run directly after starting, never serve any data at all.
References
sep@nlnetlabs.nlhttps://www.debian.org/security/2021/dsa-5033Third Party Advisory
sep@nlnetlabs.nlhttps://www.debian.org/security/2022/dsa-5041Third Party Advisory
sep@nlnetlabs.nlhttps://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txtVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2021/dsa-5033Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2022/dsa-5041Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txtVendor Advisory
Impacted products
Vendor Product Version
nlnetlabs routinator *
debian debian_linux 11.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Routinator",
          "vendor": "NLnet Labs",
          "versions": [
            {
              "lessThanOrEqual": "0.10.1",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "sep@nlnetlabs.nl"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:nlnetlabs:routinator:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "708A1431-499D-4BE0-8032-877635B61029",
              "versionEndExcluding": "0.10.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In NLnet Labs Routinator prior to 0.10.2, a validation run can be delayed significantly by an RRDP repository by not answering but slowly drip-feeding bytes to keep the connection alive. This can be used to effectively stall validation. While Routinator has a configurable time-out value for RRDP connections, this time-out was only applied to individual read or write operations rather than the complete request. Thus, if an RRDP repository sends a little bit of data before that time-out expired, it can continuously extend the time it takes for the request to finish. Since validation will only continue once the update of an RRDP repository has concluded, this delay will cause validation to stall, leading to Routinator continuing to serve the old data set or, if in the initial validation run directly after starting, never serve any data at all."
    },
    {
      "lang": "es",
      "value": "En NLnet Labs Routinator versiones anteriores a 0.10.2, una ejecuci\u00f3n de comprobaci\u00f3n puede ser retrasada significativamente por un repositorio RRDP, no respondiendo sino alimentando lentamente con bytes para mantener viva la conexi\u00f3n. Esto puede ser usado para detener efectivamente la comprobaci\u00f3n. Mientras que Routinator presenta un valor de tiempo de espera configurable para las conexiones RRDP, este tiempo de espera s\u00f3lo se aplicaba a las operaciones individuales de lectura o escritura y no a la petici\u00f3n completa. Por lo tanto, si un repositorio RRDP env\u00eda un poco de datos antes de que el tiempo de espera expire, puede extender continuamente el tiempo que toma para que la petici\u00f3n termine. Dado que la comprobaci\u00f3n s\u00f3lo continuar\u00e1 una vez que la actualizaci\u00f3n de un repositorio RRDP haya concluido, este retraso causar\u00e1 que la comprobaci\u00f3n se detenga, conllevando a que Routinator contin\u00fae sirviendo el antiguo conjunto de datos o, si en la comprobaci\u00f3n inicial se ejecuta directamente despu\u00e9s de comenzar, nunca sirva ning\u00fan dato"
    }
  ],
  "id": "CVE-2021-43173",
  "lastModified": "2026-06-17T04:10:35.000",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 5.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-11-09T17:15:07.733",
  "references": [
    {
      "source": "sep@nlnetlabs.nl",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-5033"
    },
    {
      "source": "sep@nlnetlabs.nl",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2022/dsa-5041"
    },
    {
      "source": "sep@nlnetlabs.nl",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txt"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-5033"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2022/dsa-5041"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txt"
    }
  ],
  "sourceIdentifier": "sep@nlnetlabs.nl",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-755"
        }
      ],
      "source": "sep@nlnetlabs.nl",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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