CVE-2021-1706
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 · uneditedWindows LUAFV Elevation of Privilege 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 · moderate confidenceCVE-2021-1706 is an Elevation of Privilege vulnerability in Windows LUAFV (Lua File Virtualization), a component used for application compatibility. The vulnerability allows a local attacker to gain elevated privileges on the affected system.
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= 20h2= 1607= 1803= 1809= 1909= 2004all versionsall versionsall versions= r2all versions= r2all 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
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
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Check Windows versionRun 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to identify the installed Windows version and build numberAffected if The version matches any of the following: Windows 10 versions 1607, 1803, 1809, 1909, 2004, 20h2; Windows 7 (any version); Windows 8.1 (any version); Windows RT 8.1; Windows Server 2008 R2; Windows Server 2012 or 2012 R2; Windows Server 2016; Windows Server 2019
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Verify LUAFV driver presenceCheck if luafv.sys exists in the system drivers directory (typically C:\Windows\System32\drivers\luafv.sys) using File Explorer or 'dir C:\Windows\System32\drivers\luafv.sys'Affected if The luafv.sys file is present on the system - LUAFV is a built-in Windows component for application compatibility and is included in affected versions
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Confirm LUAFV is loadedOpen Services (services.msc) and look for the 'luafv' service, or run 'sc query luafv' from an elevated command prompt to check service statusAffected if The LUAFV service exists and is running (state shows SERVICE_RUNNING) - the vulnerability requires this component to be active
If the system runs an affected Windows version AND the LUAFV component is present and loaded, the environment is vulnerable to local privilege escalation via CVE-2021-1706.
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.
From vendor dataApply the Microsoft security update for CVE-2021-1706, which is included in the January 2021 Windows security updates. Prioritize patching systems where untrusted users have local access.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 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 $2,560.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-1706 — 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-2021-1706 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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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.
- 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