How severe is CVE-1999-0918?

CVE-1999-0918 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-1999-0918 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 30% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-0918?

CVE-1999-0918 primarily affects Microsoft Windows 2000. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-1999-0918?

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-1999-0918 published?

CVE-1999-0918 was published on 1999-07-03 and last updated on 2026-06-16.

CVE-1999-0918

CVE-1999-0918 is a high-severity vulnerability in Microsoft Windows 2000 with a CVSS 2.0 base score of 7.8. Its EPSS exploit-prediction score of 30% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 2.0 base score 7.8)
EPSS exploit prediction: 30% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Windows 2000
Published: 1999-07-03
Last modified: 2026-06-16

Description

Denial of service in various Windows systems via malformed, fragmented IGMP packets.

Frequently asked questions

What is CVE-1999-0918?: Denial of service in various Windows systems via malformed, fragmented IGMP packets.
How severe is CVE-1999-0918?: CVE-1999-0918 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-1999-0918 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 30% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-0918?: CVE-1999-0918 primarily affects Microsoft Windows 2000. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-1999-0918?: 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-1999-0918 published?: CVE-1999-0918 was published on 1999-07-03 and last updated on 2026-06-16.

References

Affected products (9)

cpe:2.3:o:microsoft:windows_2000:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_95:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_98:*:gold:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_nt:4.0:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_nt:4.0:sp1:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_nt:4.0:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_nt:4.0:sp3:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_nt:4.0:sp4:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_nt:4.0:sp5:*:*:*:*:*:*

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