Windows 2003 ServerOperating system · Microsoft

CVE-2011-0671

HIGH · 8.4 CVSS v3.1 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 →
89/100
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 exploiting incorrect driver object management. The flaw enables a crafted application to manipulate freed memory objects in the Windows kernel.

MitigationApply Microsoft security update MS11-034 to all affected Windows systems. This is a kernel-level vulnerability requiring OS patching; no workarounds are available.

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
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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' from Start > Run, or execute 'systeminfo' in Command Prompt and look at the OS Name and Version line
    Affected if The version listed is Windows XP, Vista, Windows 7, Windows Server 2003, Windows Server 2008, or Windows Server 2008 R2 - these are all in the affected product list
  2. Verify win32k.sys driver is present
    Check that the file C:\Windows\System32\win32k.sys exists on the system - this is the vulnerable driver component
    Affected if The file exists; the vulnerability resides in this kernel driver
  3. Check if MS11-034 security update is installed
    Run 'wmic qfe list' or open Control Panel > Programs > View installed updates and search for 'MS11-034' or security update for Windows (typically dated May 10, 2011)
    Affected if The MS11-034 update is NOT listed in installed updates - the system remains vulnerable if unpatched
  4. Confirm kernel privilege context
    This is a kernel-level vulnerability; the exploit requires a local authenticated user to execute code. Check if untrusted local users have access to run executables on the system
    Affected if Local unprivileged users can run executables on the system and the MS11-034 update is missing - exploitation is possible

The system is affected if it runs any Windows XP, Vista, 7, Server 2003, Server 2008, or Server 2008 R2 version AND the MS11-034 security update is not installed.

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 to all affected Windows systems. This is a kernel-level vulnerability requiring OS patching; no workarounds are available.

Fix this in Windows 2003 Server Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing2.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,340
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2011-0671 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2011-0671 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