How severe is CVE-2003-0503?

CVE-2003-0503 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2003-0503 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2003-0503?

CVE-2003-0503 affects Microsoft Windows 2000. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2003-0503?

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-2003-0503 published?

CVE-2003-0503 was published on 2003-08-07 and last updated on 2026-06-16.

CVE-2003-0503

CVE-2003-0503 is a high-severity vulnerability in Microsoft Windows 2000 with a CVSS 2.0 base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 2.0 base score 7.5)
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Windows 2000
Published: 2003-08-07
Last modified: 2026-06-16

Description

Buffer overflow in the ShellExecute API function of SHELL32.DLL in Windows 2000 before SP4 may allow attackers to cause a denial of service or execute arbitrary code via a long third argument.

Frequently asked questions

What is CVE-2003-0503?: Buffer overflow in the ShellExecute API function of SHELL32.DLL in Windows 2000 before SP4 may allow attackers to cause a denial of service or execute arbitrary code via a long third argument.
How severe is CVE-2003-0503?: CVE-2003-0503 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2003-0503 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2003-0503?: CVE-2003-0503 affects Microsoft Windows 2000. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2003-0503?: 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-2003-0503 published?: CVE-2003-0503 was published on 2003-08-07 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:o:microsoft:windows_2000:*:sp3:*:*:*:*:*:*

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