CVE-2009-1926
CVE-2009-1926 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 35% places it in the 98th percentile, indicating an elevated likelihood of exploitation.
Key facts
- Severity: High (CVSS 2.0 base score 7.8)
- EPSS exploit prediction: 35% (98th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Microsoft Windows 2000
- Published:
- Last modified:
Description
Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server 2008 Gold and SP2 allow remote attackers to cause a denial of service (TCP outage) via a series of TCP sessions that have pending data and a (1) small or (2) zero receive window size, and remain in the FIN-WAIT-1 or FIN-WAIT-2 state indefinitely, aka "TCP/IP Orphaned Connections Vulnerability."
Frequently asked questions
- What is CVE-2009-1926?
- Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server 2008 Gold and SP2 allow remote attackers to cause a denial of service (TCP outage) via a series of TCP sessions that have pending data and a (1) small or (2) zero receive window size, and remain in the FIN-WAIT-1 or FIN-WAIT-2 state indefinitely, aka "TCP/IP Orphaned Connections Vulnerability."
- How severe is CVE-2009-1926?
- CVE-2009-1926 has a CVSS 2.0 base score of 7.8, rated high severity.
- Is CVE-2009-1926 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 35% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2009-1926?
- CVE-2009-1926 primarily affects Microsoft Windows 2000. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2009-1926?
- 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-2009-1926 published?
- CVE-2009-1926 was published on 2009-09-08 and last updated on 2026-06-16.
References
- http://osvdb.org/57797
- http://www.recurity-labs.com/content/pub/Microsoft_Windows_CVE-2009-1926
- http://www.securityfocus.com/archive/1/506331/100/0/threaded
- http://www.securityfocus.com/bid/36269
- http://www.us-cert.gov/cas/techalerts/TA09-251A.html
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-048
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5965
Affected products (17)
- cpe:2.3:o:microsoft:windows_2000:-:sp4:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2003:*:sp2:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:*:*:itanium:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:-:-:x32:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:-:-:x64:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:-:sp2:itanium:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:-:sp2:x64:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:-:sp2:x86:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_vista:*:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_vista:*:sp1:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_vista:*:sp2:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_vista:-:-:x64:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_vista:-:sp1:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_vista:-:sp2:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_xp:*:sp2:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_xp:*:sp2:professional:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_xp:*:sp3:*:*:*:*:*:*
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