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FKIE_CVE-2021-22212

Vulnerability from fkie_nvd - Published: 2021-06-08 13:15 - Updated: 2026-06-17 03:36
Severity
4.0 (Medium) - CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N
7.4 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Summary
ntpkeygen can generate keys that ntpd fails to parse. NTPsec 1.2.0 allows ntpkeygen to generate keys with '#' characters. ntpd then either pads, shortens the key, or fails to load these keys entirely, depending on the key type and the placement of the '#'. This results in the administrator not being able to use the keys as expected or the keys are shorter than expected and easier to brute-force, possibly resulting in MITM attacks between ntp clients and ntp servers. For short AES128 keys, ntpd generates a warning that it is padding them.
References
cve@gitlab.comhttps://bugzilla.redhat.com/show_bug.cgi?id=1955859Issue Tracking, Patch, Third Party Advisory
cve@gitlab.comhttps://gitlab.com/NTPsec/ntpsec/-/issues/699Issue Tracking, Patch, Third Party Advisory
cve@gitlab.comhttps://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22212.jsonThird Party Advisory
cve@gitlab.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3GIT2HYL5BQXPGKI6ZDNG473IEQ5WQF2/
af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=1955859Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/NTPsec/ntpsec/-/issues/699Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22212.jsonThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3GIT2HYL5BQXPGKI6ZDNG473IEQ5WQF2/
Impacted products
Vendor Product Version
ntpsec ntpsec 1.2.0
fedoraproject fedora 34
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "ntpsec",
          "vendor": "NTPsec",
          "versions": [
            {
              "status": "affected",
              "version": "=1.2.0"
            }
          ]
        }
      ],
      "source": "cve@gitlab.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:ntpsec:ntpsec:1.2.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "7017EBAD-09C2-4FD3-9EE5-FF0C5861C788",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "ntpkeygen can generate keys that ntpd fails to parse. NTPsec 1.2.0 allows ntpkeygen to generate keys with \u0027#\u0027 characters. ntpd then either pads, shortens the key, or fails to load these keys entirely, depending on the key type and the placement of the \u0027#\u0027. This results in the administrator not being able to use the keys as expected or the keys are shorter than expected and easier to brute-force, possibly resulting in MITM attacks between ntp clients and ntp servers. For short AES128 keys, ntpd generates a warning that it is padding them."
    },
    {
      "lang": "es",
      "value": "ntpkeygen puede generar claves que ntpd no puede analizar. NTPsec versi\u00f3n 1.2.0 permite a ntpkeygen generar claves con caracteres \"#\". ntpd entonces rellena, acorta la clave, o comete un fallo al cargar estas claves por completo, dependiendo del tipo de clave y la colocaci\u00f3n del \"#\". Esto hace que el administrador no pueda usar las claves como se esperaba o que las claves sean m\u00e1s cortas de lo esperado y m\u00e1s f\u00e1ciles de forzar, resultando posiblemente en ataques MITM entre clientes ntp y servidores ntp. Para claves AES128 cortas, ntpd genera una advertencia de que las est\u00e1 rellenando"
    }
  ],
  "id": "CVE-2021-22212",
  "lastModified": "2026-06-17T03:36:48.917",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 5.8,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 4.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
          "baseScore": 4.0,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 0.3,
        "impactScore": 3.6,
        "source": "cve@gitlab.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 5.2,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-06-08T13:15:07.567",
  "references": [
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1955859"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/NTPsec/ntpsec/-/issues/699"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22212.json"
    },
    {
      "source": "cve@gitlab.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3GIT2HYL5BQXPGKI6ZDNG473IEQ5WQF2/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1955859"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/NTPsec/ntpsec/-/issues/699"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22212.json"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3GIT2HYL5BQXPGKI6ZDNG473IEQ5WQF2/"
    }
  ],
  "sourceIdentifier": "cve@gitlab.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-327"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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