CVE-2011-0033

CVE-2011-0033 is a critical-severity vulnerability in Microsoft Windows 2003 Server with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 21% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

• Severity: Critical (CVSS 2.0 base score 9.3)
• EPSS exploit prediction: 21% (97th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Microsoft Windows 2003 Server
• Published: 2011-02-10
• Last modified: 2026-06-16

Description

The OpenType Compact Font Format (CFF) driver in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, and R2, and Windows 7 does not properly validate parameter values in OpenType fonts, which allows remote attackers to execute arbitrary code via a crafted font, aka "OpenType Font Encoded Character Vulnerability."

Frequently asked questions

What is CVE-2011-0033?

The OpenType Compact Font Format (CFF) driver in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, and R2, and Windows 7 does not properly validate parameter values in OpenType fonts, which allows remote attackers to execute arbitrary code via a crafted font, aka "OpenType Font Encoded Character Vulnerability."

How severe is CVE-2011-0033?

CVE-2011-0033 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2011-0033 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 21% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-0033?

CVE-2011-0033 primarily affects Microsoft Windows 2003 Server. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-0033?

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-2011-0033 published?

CVE-2011-0033 was published on 2011-02-10 and last updated on 2026-06-16.

References

• http://osvdb.org/70821
• http://secunia.com/advisories/43252
• http://support.avaya.com/css/P8/documents/100127239
• http://www.securityfocus.com/bid/46106
• http://www.securitytracker.com/id?1025034
• http://www.vupen.com/english/advisories/2011/0320
• https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-007
• https://exchange.xforce.ibmcloud.com/vulnerabilities/64906
• https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11593

Affected products (18)

• 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:*:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_7:-:*:*:*:*:*:*:*
• 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:*:r2:itanium:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server_2008:*:r2: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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