How severe is CVE-2009-1920?

CVE-2009-1920 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-1920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 22% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-1920?

CVE-2009-1920 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-2009-1920?

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-2009-1920 published?

CVE-2009-1920 was published on 2009-09-08 and last updated on 2026-06-16.

CVE-2009-1920

CVE-2009-1920 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 22% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-94.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 22% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Microsoft Windows 2000
Published: 2009-09-08
Last modified: 2026-06-16

Description

The JScript scripting engine 5.1, 5.6, 5.7, and 5.8 in JScript.dll in Microsoft Windows, as used in Internet Explorer, does not properly load decoded scripts into memory before execution, which allows remote attackers to execute arbitrary code via a crafted web site that triggers memory corruption, aka "JScript Remote Code Execution Vulnerability."

Frequently asked questions

What is CVE-2009-1920?: The JScript scripting engine 5.1, 5.6, 5.7, and 5.8 in JScript.dll in Microsoft Windows, as used in Internet Explorer, does not properly load decoded scripts into memory before execution, which allows remote attackers to execute arbitrary code via a crafted web site that triggers memory corruption, aka "JScript Remote Code Execution Vulnerability."
How severe is CVE-2009-1920?: CVE-2009-1920 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-1920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 22% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-1920?: CVE-2009-1920 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-2009-1920?: 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-2009-1920 published?: CVE-2009-1920 was published on 2009-09-08 and last updated on 2026-06-16.

References

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:professional_x64:*:*:*:*:*
cpe:2.3:o:microsoft:windows_xp:-:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_xp:-:sp3:*:*:*:*:*:*

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-94 (Code Injection) vulnerabilities

CVE-2026-57624 — Critical (CVSS 10.0): Unauthenticated Remote Code Execution (RCE) in Blocksy Companion Pro <= 2.1.46 versions.
CVE-2026-10134 — Critical (CVSS 10.0): IBM Langflow OSS 1.0.0 through 1.9.3 allows an attacker to read every secret available to the Langflow process, read…
CVE-2026-53576 — Critical (CVSS 10.0): Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the authentication filter…
CVE-2026-10561 — Critical (CVSS 10.0): IBM Langflow OSS 1.0.0 through 1.9.3 has an vulnerability due to an improper isolation of Python execution combined…
CVE-2026-25470 — Critical (CVSS 10.0): Improper Control of Generation of Code ('Code Injection') vulnerability in ACPT ACPT (Pro) - Custom Post Types Plugin…
CVE-2026-48836 — Critical (CVSS 10.0): Unauthenticated Remote Code Execution (RCE) in Easy Invoice <= 2.1.19 versions.

Browse all CWE-94 (Code Injection) vulnerabilities →