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FKIE_CVE-2021-39921

Vulnerability from fkie_nvd - Published: 2021-11-19 17:15 - Updated: 2026-06-17 04:04
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
NULL pointer exception in the Modbus dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
References
cve@gitlab.comhttps://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39921.jsonThird Party Advisory
cve@gitlab.comhttps://gitlab.com/wireshark/wireshark/-/issues/17703Exploit, Issue Tracking, Patch, Third Party Advisory
cve@gitlab.comhttps://lists.debian.org/debian-lts-announce/2021/12/msg00015.htmlMailing List, Third Party Advisory
cve@gitlab.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/
cve@gitlab.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/
cve@gitlab.comhttps://security.gentoo.org/glsa/202210-04Third Party Advisory
cve@gitlab.comhttps://www.debian.org/security/2021/dsa-5019Third Party Advisory
cve@gitlab.comhttps://www.wireshark.org/security/wnpa-sec-2021-14.htmlVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39921.jsonThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://gitlab.com/wireshark/wireshark/-/issues/17703Exploit, Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2021/12/msg00015.htmlMailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/
af854a3a-2127-422b-91ae-364da2661108https://security.gentoo.org/glsa/202210-04Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2021/dsa-5019Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.wireshark.org/security/wnpa-sec-2021-14.htmlVendor Advisory
Impacted products
Vendor Product Version
wireshark wireshark *
wireshark wireshark *
fedoraproject fedora 34
fedoraproject fedora 35
debian debian_linux 9.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Wireshark",
          "vendor": "Wireshark Foundation",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e=3.4.0, \u003c3.4.10"
            },
            {
              "status": "affected",
              "version": "\u003e=3.2.0, \u003c3.2.18"
            }
          ]
        }
      ],
      "source": "cve@gitlab.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:wireshark:wireshark:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D7CE273F-61E9-4B38-B83A-EE5BE6A8E2C0",
              "versionEndIncluding": "3.2.17",
              "versionStartIncluding": "3.2.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:wireshark:wireshark:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "78594687-32B9-4E00-AD24-95D76C66673B",
              "versionEndIncluding": "3.4.9",
              "versionStartIncluding": "3.4.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*",
              "matchCriteriaId": "80E516C0-98A4-4ADE-B69F-66A772E2BAAA",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "NULL pointer exception in the Modbus dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file"
    },
    {
      "lang": "es",
      "value": "Una excepci\u00f3n de puntero NULL en el disector Modbus en Wireshark versiones 3.4.0 a 3.4.9 y 3.2.0 a 3.2.17, permite una denegaci\u00f3n de servicio por medio de una inyecci\u00f3n de paquetes o de un archivo de captura dise\u00f1ado"
    }
  ],
  "id": "CVE-2021-39921",
  "lastModified": "2026-06-17T04:04:25.790",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "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": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "cve@gitlab.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-11-19T17:15:08.343",
  "references": [
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39921.json"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/wireshark/wireshark/-/issues/17703"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "https://lists.debian.org/debian-lts-announce/2021/12/msg00015.html"
    },
    {
      "source": "cve@gitlab.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/"
    },
    {
      "source": "cve@gitlab.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
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      ],
      "url": "https://security.gentoo.org/glsa/202210-04"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-5019"
    },
    {
      "source": "cve@gitlab.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.wireshark.org/security/wnpa-sec-2021-14.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39921.json"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://gitlab.com/wireshark/wireshark/-/issues/17703"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "https://lists.debian.org/debian-lts-announce/2021/12/msg00015.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      ],
      "url": "https://security.gentoo.org/glsa/202210-04"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      "url": "https://www.debian.org/security/2021/dsa-5019"
    },
    {
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      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.wireshark.org/security/wnpa-sec-2021-14.html"
    }
  ],
  "sourceIdentifier": "cve@gitlab.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

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