CVE-1999-1291

CVE-1999-1291 is a medium-severity vulnerability in Microsoft Windows 95 with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 13% places it in the 96th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

TCP/IP implementation in Microsoft Windows 95, Windows NT 4.0, and possibly others, allows remote attackers to reset connections by forcing a reset (RST) via a PSH ACK or other means, obtaining the target's last sequence number from the resulting packet, then spoofing a reset to the target.

Frequently asked questions

What is CVE-1999-1291?
TCP/IP implementation in Microsoft Windows 95, Windows NT 4.0, and possibly others, allows remote attackers to reset connections by forcing a reset (RST) via a PSH ACK or other means, obtaining the target's last sequence number from the resulting packet, then spoofing a reset to the target.
How severe is CVE-1999-1291?
CVE-1999-1291 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-1999-1291 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-1291?
CVE-1999-1291 primarily affects Microsoft Windows 95. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-1999-1291?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-1999-1291 published?
CVE-1999-1291 was published on 1998-10-05 and last updated on 2026-06-16.

References

Affected products (2)

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