How severe is CVE-2012-1866?

CVE-2012-1866 has a CVSS 2.0 base score of 7.2, rated high severity.

Is CVE-2012-1866 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-1866?

CVE-2012-1866 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-2012-1866?

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-2012-1866 published?

CVE-2012-1866 was published on 2012-06-12 and last updated on 2026-06-16.

CVE-2012-1866

CVE-2012-1866 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% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Windows 2003 Server
Published: 2012-06-12
Last modified: 2026-06-16

Description

win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 does not properly handle user-mode input passed to kernel mode for driver objects, which allows local users to gain privileges via a crafted application, aka "Clipboard Format Atom Name Handling Vulnerability."

Frequently asked questions

What is CVE-2012-1866?: win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 does not properly handle user-mode input passed to kernel mode for driver objects, which allows local users to gain privileges via a crafted application, aka "Clipboard Format Atom Name Handling Vulnerability."
How severe is CVE-2012-1866?: CVE-2012-1866 has a CVSS 2.0 base score of 7.2, rated high severity.
Is CVE-2012-1866 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-1866?: CVE-2012-1866 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-2012-1866?: 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-2012-1866 published?: CVE-2012-1866 was published on 2012-06-12 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_7:*:*:x86:*:*:*:*:*
cpe:2.3:o:microsoft:windows_7:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_7:-:sp1:x64:*:*:*:*:*
cpe:2.3:o:microsoft:windows_7:-:sp1:x86:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2003:*:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:*:r2:itanium:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:*:r2:x64:*:*:*:*:*
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:*:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_xp:*:sp3:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_xp:-:sp2:x64:*:*:*:*:*

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