CVE-2021-1697
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 InstallService 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 confidenceThis is a privilege escalation vulnerability in the Windows InstallService component. The vulnerability allows an attacker to elevate their privileges on a Windows system, potentially gaining administrator or SYSTEM-level access. It affects the Windows InstallService which handles software installation operations.
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 versions= 20h2= 1607= 1803= 1809= 1909= 2004all versions= 20h2= 1909= 2004all 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' from command prompt or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to display the installed Windows version and build numberAffected if The version displayed matches Windows 10 (any of the listed versions: 1607, 1803, 1809, 1909, 2004, 20h2) or Windows Server 2016/2019 (any version)
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Confirm InstallService component existsRun 'sc query InstallService' from an elevated command prompt to query the status of the Windows InstallServiceAffected if The service is found and displayed (even if not running, the vulnerable component is present on the system)
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Check for installed security updatesRun 'wmic qfe list' or 'Get-HotFix -Description "Security Update" | Sort-Object InstalledOn' from PowerShell to list installed security updatesAffected if No security update specifically listed for CVE-2021-1697 is installed on the system
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Verify patch status via Windows Update historyOpen Settings > Update & Security > Windows Update > View update history, or run 'powershell Get-WmiObject -Class Win32_QuickFixEngineering' to enumerate installed patchesAffected if The update history does not show KB5000822 (Windows 10 1909), KB5000802 (Windows 10 2004), KB5003171 (Windows 10 20h2), or the equivalent server-specific security update for CVE-2021-1697
A system is affected if it runs a vulnerable Windows 10 version (1607, 1803, 1809, 1909, 2004, 20h2), Windows Server 2016, or Windows Server 2019, and the CVE-2021-1697 security update has not been installed.
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-2021-1697 through Windows Update or by deploying the applicable patch via enterprise patch management tools.
- 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-2021-1697 — 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-2021-1697 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