How severe is CVE-2018-6923?

CVE-2018-6923 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-6923 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6923?

CVE-2018-6923 primarily affects Freebsd. In total, 40 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-6923?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-6923 published?

CVE-2018-6923 was published on 2018-09-04 and last updated on 2026-06-17.

CVE-2018-6923

CVE-2018-6923 is a high-severity vulnerability in Freebsd with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Freebsd
Published: 2018-09-04
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2018-6923?: 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.
How severe is CVE-2018-6923?: CVE-2018-6923 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-6923 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6923?: CVE-2018-6923 primarily affects Freebsd. In total, 40 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-6923?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-6923 published?: CVE-2018-6923 was published on 2018-09-04 and last updated on 2026-06-17.

References

Affected products (40)

cpe:2.3:o:freebsd:freebsd:2.2:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:3.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.3:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.4:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.5:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.6:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.7:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.8:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.9:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.10:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.11:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:5.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:5.1:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:5.2:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:5.3:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:5.4:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:5.5:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:6.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:6.1:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:6.2:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:6.3:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:6.4:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:7.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:7.1:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:7.2:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:7.3:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:7.4:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:8.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:8.1:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:8.2:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:8.3:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:8.4:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:9.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:9.1:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:9.2:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:9.3:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:10.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:11.0:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:11.1:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:11.2:*:*:*:*:*:*:*

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