FKIE_CVE-2002-0518

Vulnerability from fkie_nvd - Published: 2002-08-12 04:00 - Updated: 2026-06-16 21:57
Severity
Summary
The SYN cache (syncache) and SYN cookie (syncookie) mechanism in FreeBSD 4.5 and earlier allows remote attackers to cause a denial of service (crash) (1) via a SYN packet that is accepted using syncookies that causes a null pointer to be referenced for the socket's TCP options, or (2) by killing and restarting a process that listens on the same socket, which does not properly clear the old inpcb pointer on restart.
References
cve@mitre.orgftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-02:20.syncache.asc
cve@mitre.orghttp://www.iss.net/security_center/static/8873.php
cve@mitre.orghttp://www.iss.net/security_center/static/8875.phpPatch, Vendor Advisory
cve@mitre.orghttp://www.osvdb.org/6046
cve@mitre.orghttp://www.securityfocus.com/bid/4524Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-02:20.syncache.asc
af854a3a-2127-422b-91ae-364da2661108http://www.iss.net/security_center/static/8873.php
af854a3a-2127-422b-91ae-364da2661108http://www.iss.net/security_center/static/8875.phpPatch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108http://www.osvdb.org/6046
af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/4524Patch, Vendor Advisory
Impacted products
Vendor Product Version
freebsd freebsd 4.5
freebsd freebsd 4.5
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:freebsd:freebsd:4.5:release:*:*:*:*:*:*",
              "matchCriteriaId": "3D41CB12-7894-4D25-80EC-23C56171D973",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:freebsd:freebsd:4.5:stable:*:*:*:*:*:*",
              "matchCriteriaId": "09789843-6A1A-4CDB-97E8-89E82B79DDB5",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The SYN cache (syncache) and SYN cookie (syncookie) mechanism in FreeBSD 4.5 and earlier allows remote attackers to cause a denial of service (crash) (1) via a SYN packet that is accepted using syncookies that causes a null pointer to be referenced for the socket\u0027s TCP options, or (2) by killing and restarting a process that listens on the same socket, which does not properly clear the old inpcb pointer on restart."
    },
    {
      "lang": "es",
      "value": "Los mecanismos SYN cache (syncache) y SYN cookie (syncookie) en FreeBSD 4.5 y anteriores, permite a atacantes remotos provocar la Denegaci\u00f3n de Servicios (por caida) por algunos de los siguiente m\u00e9todos:\r\n\r\n mediante un paquete SYN aceptado utilizando syncookies, que provoca que las opciones TCP del conector (socket) referencien a un puntero nulo.\r\n eliminando y reiniciando un proceso que espera en el mismo conector (socket) que no elimin\u00f3 adecuadamente el contenido anterior del puntero inpcb en el reinicio."
    }
  ],
  "id": "CVE-2002-0518",
  "lastModified": "2026-06-16T21:57:35.900",
  "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
      }
    ]
  },
  "published": "2002-08-12T04:00:00.000",
  "references": [
    {
      "source": "cve@mitre.org",
      "url": "ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-02:20.syncache.asc"
    },
    {
      "source": "cve@mitre.org",
      "url": "http://www.iss.net/security_center/static/8873.php"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "http://www.iss.net/security_center/static/8875.php"
    },
    {
      "source": "cve@mitre.org",
      "url": "http://www.osvdb.org/6046"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "http://www.securityfocus.com/bid/4524"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-02:20.syncache.asc"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.iss.net/security_center/static/8873.php"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "http://www.iss.net/security_center/static/8875.php"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.osvdb.org/6046"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "http://www.securityfocus.com/bid/4524"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-Other"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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