How severe is CVE-1999-1463?

CVE-1999-1463 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-1999-1463 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 16% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-1463?

CVE-1999-1463 affects Microsoft Windows Nt. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-1999-1463?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-1999-1463 published?

CVE-1999-1463 was published on 1997-07-10 and last updated on 2026-06-16.

CVE-1999-1463

CVE-1999-1463 is a medium-severity vulnerability in Microsoft Windows Nt with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 16% places it in the 97th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 16% (97th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Windows Nt
Published: 1997-07-10
Last modified: 2026-06-16

Description

Windows NT 4.0 before SP3 allows remote attackers to bypass firewall restrictions or cause a denial of service (crash) by sending improperly fragmented IP packets without the first fragment, which the TCP/IP stack incorrectly reassembles into a valid session.

Frequently asked questions

What is CVE-1999-1463?: Windows NT 4.0 before SP3 allows remote attackers to bypass firewall restrictions or cause a denial of service (crash) by sending improperly fragmented IP packets without the first fragment, which the TCP/IP stack incorrectly reassembles into a valid session.
How severe is CVE-1999-1463?: CVE-1999-1463 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-1999-1463 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 16% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-1463?: CVE-1999-1463 affects Microsoft Windows Nt. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-1999-1463?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-1999-1463 published?: CVE-1999-1463 was published on 1997-07-10 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:o:microsoft:windows_nt:*:sp3:*:*:*:*:*:*

More vulnerabilities in Microsoft Windows Nt

CVE-2005-0050 — Critical (CVSS 10.0): The License Logging service for Windows NT Server, Windows 2000 Server, and Windows Server 2003 does not properly…
CVE-2004-0571 — Critical (CVSS 10.0): Microsoft Word for Windows 6.0 Converter does not properly validate certain data lengths, which allows remote attackers…
CVE-2004-1080 — Critical (CVSS 10.0): The WINS service (wins.exe) on Microsoft Windows NT Server 4.0, Windows 2000 Server, and Windows Server 2003 allows…
CVE-2004-0568 — Critical (CVSS 10.0): HyperTerminal application for Windows NT 4.0, Windows 2000, Windows XP, and Windows Server 2003 does not properly…
CVE-2004-0901 — Critical (CVSS 10.0): Microsoft Word for Windows 6.0 Converter (MSWRD632.WPC), as used in WordPad, does not properly validate certain data…
CVE-2004-0900 — Critical (CVSS 10.0): The DHCP Server service for Microsoft Windows NT 4.0 Server and Terminal Server Edition does not properly validate the…

All CVEs affecting Microsoft Windows Nt →