dbcve.org
Windows 2003 ServerOperating system · Microsoft

CVE-2011-1242

HIGH · 7.2 CVSS v2.0 Published 2011-04-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
77/100
Remediation priority · High
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
Use-after-free vulnerability in win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 allows local users to gain privileges via a crafted application that leverages incorrect driver object management, a different vulnerability than other "Vulnerability Type 1" CVEs listed in MS11-034, aka "Win32k Use After Free 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

Use-after-free vulnerability in win32k.sys kernel-mode driver allows local authenticated attackers to escalate privileges to SYSTEM level by leveraging incorrect driver object management. The flaw enables a specially crafted application to manipulate freed memory objects in the Windows kernel, achieving arbitrary code execution with kernel privileges.

MitigationApply Microsoft security update MS11-034 which patches the win32k.sys use-after-free vulnerability; for end-of-life systems unable to receive the patch, implement compensating controls such as restricting local user permissions and deploying endpoint detection tools.

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= r2
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
Local
Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete

AV:L/AC:L/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. Confirm Windows version is in the affected range
    Run 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to identify the Windows edition and version
    Affected if The system runs Windows XP, Vista, Windows 2003 Server, Windows 2008, Windows 2008 R2, or Windows 7 (any version within these families)
  2. Verify MS11-034 security update is installed
    Run 'wmic qfe list' or check 'Control Panel > Programs > View installed updates' for security update KB952954
    Affected if The security update KB952954 (MS11-034) is NOT installed or shows as missing
  3. Check win32k.sys file version
    Navigate to C:\Windows\System32\drivers\win32k.sys, right-click and select Properties, or run 'dir C:\Windows\System32\drivers\win32k.sys' to view version and date
    Affected if The win32k.sys version is older than the version provided by MS11-034 for your specific Windows version, or the file date predates the patch release (April 2011)
  4. Verify Driver Object management state (advanced)
    Use Kernel Debugger (kd.exe) or run 'lm m win32k' in WinDbg to inspect driver object reference counts; look for signs of improper object lifetime management
    Affected if Driver objects in win32k.sys show abnormal reference counts or were previously freed and not reinitialized, indicating the vulnerability is present

A system is affected if it runs any unpatched version of Windows XP, Vista, 2003, 2008, 2008 R2, or 7 AND is missing the MS11-034 update KB952954, allowing local privilege escalation via the win32k.sys use-after-free.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Microsoft security update MS11-034 which patches the win32k.sys use-after-free vulnerability; for end-of-life systems unable to receive the patch, implement compensating controls such as restricting local user permissions and deploying endpoint detection tools.

Fix this in Windows 2003 Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
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Scan for this in your stack

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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-2011-1242 in production — separate from our analysis above.

No notes yet

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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