dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 24 Mar 2022.
Windows 2000Operating system · Microsoft

CVE-2009-1123

HIGH · 7.8 CVSS v3.1 Published 2009-06-10
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
97/100
Remediation priority · Urgent
In the wild No privileges Patch available

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 kernel in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server 2008 SP2 does not properly validate changes to unspecified kernel objects, which allows local users to gain privileges via a crafted application, aka "Windows Kernel Desktop 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

This is a local privilege escalation vulnerability in the Windows kernel where improper validation of changes to unspecified kernel objects allows a local attacker to gain elevated privileges through a crafted application. The flaw affects multiple Windows versions from 2000 through Server 2008.

MitigationApply Microsoft security patch MS09-025 which addresses this kernel vulnerability. For legacy systems no longer supported by Microsoft, implement compensating controls such as restricting local user permissions, application whitelisting, or network isolation.

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 2000Operating 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
Local
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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' or check System Properties to determine the exact Windows version and build number
    Affected if Running Windows 2000, Windows XP, Windows Server 2003, Windows Vista, or Windows Server 2008 (all versions)
  2. Confirm patch MS09-025 installation
    Open Control Panel > Programs and Features > View installed updates, or run 'wmic qfe list' command to list installed hotfixes, and search for KB961371 (the patch for this vulnerability)
    Affected if The security update KB961371 is NOT installed
  3. Check user account context
    Run 'whoami /all' or 'whoami /groups' to see current user privileges and group memberships
    Affected if Running as a standard user or unprivileged account on an unpatched affected system (privilege escalation only matters for low-privilege attackers)
  4. Verify local user permissions
    Run 'net user' or check Local Users and Groups (lusrmgr.msc) to enumerate local user accounts
    Affected if Untrusted or low-privilege local accounts exist on an unpatched system, which could exploit this flaw

You are affected if you are running any unpatched version of Windows 2000, XP, Vista, Server 2003, or Server 2008 and have untrusted local users on the system.

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
Patch available Apply the vendor patch
Vendor patch docs.microsoft.com →
Interim mitigation

Apply Microsoft security patch MS09-025 which addresses this kernel vulnerability. For legacy systems no longer supported by Microsoft, implement compensating controls such as restricting local user permissions, application whitelisting, or network isolation.

Recommended fix High confidence

Apply MS09-025 security update; for end-of-life systems (Windows 2000, Windows XP post-support), upgrade to Windows 7 or later with current security updates

  1. Apply Microsoft Security Bulletin MS09-025, which addresses this kernel vulnerability and multiple related issues
  2. For Windows XP systems: Ensure SP3 is applied, then install MS09-025 security update from Microsoft Update or Windows Update
  3. For Windows Server 2003 SP2: Install MS09-025 security update from Microsoft Update or Windows Update
  4. For Windows Vista systems: Install MS09-025 security update from Microsoft Update or Windows Update
  5. For Windows Server 2008 SP2: Install MS09-025 security update from Microsoft Update or Windows Update
  6. After applying the update, restart the affected systems to complete the remediation
  7. Note: Windows 2000 SP4 reached end of life and did not receive an official patch for this vulnerability; upgrade to a supported operating system
Caveat Windows 2000 has no patch available; Windows XP mainstream support ended in 2009 and extended support ended in 2014, so upgrading to a supported OS is recommended

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

Fix this in Windows 2000 Exploited in the wild — priority engagement
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing3.0 h
  • Review / QA2.0 h
17.0 hours of engineering $3,050
Get it fixed fast

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,880.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2009-1123 — 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-2009-1123 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