How severe is CVE-2011-0087?

CVE-2011-0087 has a CVSS 2.0 base score of 7.2, rated high severity.

Is CVE-2011-0087 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-0087?

CVE-2011-0087 primarily affects Microsoft Windows 2003 Server. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-0087?

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-2011-0087 published?

CVE-2011-0087 was published on 2011-02-09 and last updated on 2026-06-16.

CVE-2011-0087

CVE-2011-0087 is a high-severity vulnerability in Microsoft Windows 2003 Server with a CVSS 2.0 base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 2.0 base score 7.2)
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Windows 2003 Server
Published: 2011-02-09
Last modified: 2026-06-16

Description

win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Server 2003 SP2, Vista SP1 and SP2, and Server 2008 Gold and SP2 does not properly validate user-mode input, which allows local users to gain privileges via a crafted application, aka "Win32k Insufficient User Input Validation Vulnerability."

Frequently asked questions

What is CVE-2011-0087?: win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Server 2003 SP2, Vista SP1 and SP2, and Server 2008 Gold and SP2 does not properly validate user-mode input, which allows local users to gain privileges via a crafted application, aka "Win32k Insufficient User Input Validation Vulnerability."
How severe is CVE-2011-0087?: CVE-2011-0087 has a CVSS 2.0 base score of 7.2, rated high severity.
Is CVE-2011-0087 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-0087?: CVE-2011-0087 primarily affects Microsoft Windows 2003 Server. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-0087?: 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-2011-0087 published?: CVE-2011-0087 was published on 2011-02-09 and last updated on 2026-06-16.

References

Affected products (14)

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_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:x32:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:*:sp2:x64:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:itanium:*:*:*:*:*
cpe:2.3:o:microsoft:windows_vista:*:sp1:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_vista:*:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_vista:-:sp1:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_xp:*:sp3:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_xp:-:sp2:x64:*:*:*:*:*

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