dbcve.org
Windows 2003 ServerOperating system · Microsoft

CVE-2011-0033

HIGH · 9.3 CVSS v2.0 Published 2011-02-10
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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."

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The OpenType Compact Font Format (CFF) driver in Windows fails to properly validate parameter values in OpenType fonts. Attackers can craft malicious font files that, when opened by a user, cause the font driver to execute arbitrary code with the user's privileges.

MitigationApply Microsoft security updates (MS11-021, MS11-027) to all affected Windows systems and restrict font loading from untrusted sources via group policy.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Windows 2003 ServerOperating system
Affected:all versions
Windows 7Operating system
Affected:all versions
Windows Server 2003Operating system
Affected:all versions
Windows Server 2008Operating system
Affected:all versions
Windows VistaOperating system
Affected:all versions
Windows XpOperating system
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
M
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete

AV:N/AC:M/Au:N/C:C/I:C/A:C

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Windows version
    Run 'winver' or check system properties to determine the exact Windows version
    Affected if The system runs Windows XP, Vista, Windows 7, Windows Server 2003, or Windows Server 2008 (all versions of these products are affected)
  2. Verify security update MS11-021 is installed
    Check Windows Update history or enumerate installed updates using 'wmic qfe list' or check the Microsoft Security Bulletin MS11-021
    Affected if The update MS11-021 is NOT installed - this is the primary detection method
  3. Verify security update MS11-027 is installed
    Check Windows Update history or enumerate installed updates using 'wmic qfe list' - MS11-027 is a subsequent update that also addresses this vulnerability
    Affected if Neither MS11-021 nor MS11-027 is installed
  4. Inspect OpenType CFF driver file version
    Locate the font driver files (fnt*.fon or related CFF driver files in System32) and check their file version properties. The vulnerable driver does not properly validate font parameters.
    Affected if The driver file version is older than the patched versions released in MS11-021 (February 2011)

The system is affected if it runs an affected Windows version (XP, Vista, 7, Server 2003, Server 2008) AND lacks both security updates MS11-021 and MS11-027.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Microsoft security updates (MS11-021, MS11-027) to all affected Windows systems and restrict font loading from untrusted sources via group policy.

Recommended fix High confidence
  1. Apply Microsoft Security Bulletin MS11-023, which addresses this OpenType Font Encoded Character Vulnerability (CVE-2011-0033)
  2. For Windows XP SP2/SP3: Ensure Windows Update is enabled and install security update KB2478971
  3. For Windows Server 2003 SP2: Install security update KB2478971 from Microsoft Update
  4. For Windows Vista SP1/SP2: Install security update KB2478971
  5. For Windows Server 2008 Gold/SP2: Install security update KB2478971
  6. For Windows 7: Install security update KB2478971
  7. After applying the update, restart the affected system to complete the remediation
  8. Verify the update was successfully installed by checking the installed updates or using the System Properties window
Caveat These are legacy operating systems no longer supported by Microsoft; consider migrating to a supported Windows version for ongoing security support

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Windows 2003 Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,080
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,328.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2011-0033 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2011-0033 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data