How severe is CVE-2009-1923?

CVE-2009-1923 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-1923 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-1923?

CVE-2009-1923 primarily affects Microsoft Windows 2000. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-1923?

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

When was CVE-2009-1923 published?

CVE-2009-1923 was published on 2009-08-12 and last updated on 2026-06-16.

CVE-2009-1923

CVE-2009-1923 is a critical-severity vulnerability in Microsoft Windows 2000 with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 25% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 25% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Microsoft Windows 2000
Published: 2009-08-12
Last modified: 2026-06-16

Description

Heap-based buffer overflow in the Windows Internet Name Service (WINS) component for Microsoft Windows 2000 SP4 and Server 2003 SP2 allows remote attackers to execute arbitrary code via a crafted WINS replication packet that triggers an incorrect buffer-length calculation, aka "WINS Heap Overflow Vulnerability."

Frequently asked questions

What is CVE-2009-1923?: Heap-based buffer overflow in the Windows Internet Name Service (WINS) component for Microsoft Windows 2000 SP4 and Server 2003 SP2 allows remote attackers to execute arbitrary code via a crafted WINS replication packet that triggers an incorrect buffer-length calculation, aka "WINS Heap Overflow Vulnerability."
How severe is CVE-2009-1923?: CVE-2009-1923 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-1923 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-1923?: CVE-2009-1923 primarily affects Microsoft Windows 2000. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-1923?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2009-1923 published?: CVE-2009-1923 was published on 2009-08-12 and last updated on 2026-06-16.

References

Affected products (4)

cpe:2.3:o:microsoft:windows_2000:*:sp4:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_2003_server:-:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_2003_server:-:sp2:itanium:*:*:*:*:*
cpe:2.3:o:microsoft:windows_2003_server:-:sp2:x64:*:*:*:*:*

More vulnerabilities in Microsoft Windows 2000

CVE-2010-0269 — Critical (CVSS 10.0): The SMB client in Microsoft Windows 2000 SP4, Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista Gold, SP1,…
CVE-2010-0231 — Critical (CVSS 10.0): The SMB implementation in the Server service in Microsoft Windows 2000 SP4, Windows XP SP2 and SP3, Windows Server 2003…
CVE-2009-3677 — Critical (CVSS 10.0): The Internet Authentication Service (IAS) in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold…
CVE-2009-2523 — Critical (CVSS 10.0): The License Logging Server (llssrv.exe) in Microsoft Windows 2000 SP4 allows remote attackers to execute arbitrary code…
CVE-2009-1925 — Critical (CVSS 10.0): The TCP/IP implementation in Microsoft Windows Vista Gold, SP1, and SP2 and Server 2008 Gold and SP2 does not properly…
CVE-2009-1930 — Critical (CVSS 10.0): The Telnet service in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server…

All CVEs affecting Microsoft Windows 2000 →

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…
CVE-2025-1866 — Critical (CVSS 10.0): Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows…
CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.

Browse all CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities →