CVE-2019-0859
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 · uneditedAn elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0803.
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 · moderate confidenceA local elevation of privilege vulnerability in the Windows Win32k kernel component (win32k.sys) where improper memory object handling allows a low-privileged user to gain SYSTEM-level access. This is a kernel-mode graphics subsystem flaw exploitable via local code execution.
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 dataall versionsall versionsall versionsall versionsall versionsall versionsall versionsall versionsCVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify Windows versionRun 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to determine the installed Windows edition and versionAffected if The version matches Windows 10 1507, 1607, 1703, 1709, 1803, 1809, Windows 7, or Windows 8.1 (any build)
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Verify security update KB4487029 is installedRun 'wmic qfe get hotfixid,installedon | findstr KB4487029' or check Windows Update history for the presence of KB4487029Affected if The update KB4487029 (or a superseded patch containing it) is NOT installed on the system
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Check win32k.sys file version as secondary verificationLocate win32k.sys in C:\Windows\System32\drivers\ and review the File Version property, or run 'powershell (Get-Item C:\Windows\System32\drivers\win32k.sys).VersionInfo.FileVersion'Affected if The file version is lower than the patched version for your specific Windows build and the system remains unpatched
A system is affected if it runs any of the listed Windows versions (10 1507-1809, 7, or 8.1) AND lacks the KB4487029 security update, leaving the win32k.sys vulnerability exposed to local privilege escalation.
Generated from the published advisory. Verify against your own configuration.
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 · scopedApply the Microsoft security update KB4487029 (or subsequent superseded patch) to all affected Windows systems. Prioritize domain controllers and servers given the privilege escalation risk.
- Open Windows Update (Settings > Update & Security > Windows Update) and check for available updates
- Install the April 2019 Security Updates (or later) for your Windows version
- If automatic updates are disabled, manually download the specific update from the Microsoft Update Catalog: https://catalog.update.microsoft.com/
- Search for KB4493464 (Windows 7/8.1) or the corresponding April 2019 security update for your Windows 10 version
- Restart the system after installing the update to ensure the Win32k.sys component is properly updated
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2019-0859 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2019-0859 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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
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