CVE-2018-6923

Status: ModifiedHigh (7.5)—
In FreeBSD before 11.1-STABLE, 11.2-RELEASE-p2, 11.1-RELEASE-p13, ip fragment reassembly code is vulnerable to a denial of service due to excessive system resource consumption. This issue can allow a remote attacker who is able to send an arbitrary ip fragments to cause the machine to consume excessive resources.
CVSS

Version: 3.0
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base score: 7.5
Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 4.01%
Percentile among all scored CVEs: 90
Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)

Freebsd — Freebsd
CWEs

CWE-400
References

Raw JSON (NVD)

Show
{
  "id": "CVE-2018-6923",
  "cveTags": [],
  "metrics": {
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          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:C",
          "authentication": "NONE",
          "integrityImpact": "NONE",
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          "availabilityImpact": "COMPLETE",
          "confidentialityImpact": "NONE"
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          "attackComplexity": "LOW",
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        "impactScore": 3.6,
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  "affected": [
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  "published": "2018-09-04T18:29:00.610",
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      "value": "In FreeBSD before 11.1-STABLE, 11.2-RELEASE-p2, 11.1-RELEASE-p13, ip fragment reassembly code is vulnerable to a denial of service due to excessive system resource consumption. This issue can allow a remote attacker who is able to send an arbitrary ip fragments to cause the machine to consume excessive resources."
    },
    {
      "lang": "es",
      "value": "En FreeBSD en versiones anteriores a la 11.1-STABLE, 11.2-RELEASE-p2 y 11.1-RELEASE-p13, el código de reensamblado de fragmentos de ip es vulnerable a una denegación de servicio (DoS) debido al consumo excesivo de recursos del sistema. Este problema puede permitir que un atacante remoto que pueda enviar fragmentos de ip arbitrarios haga que la máquina consuma demasiados recursos."
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  "lastModified": "2026-06-17T02:02:28.187",
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