CVE-2026-26170
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 · uneditedImproper input validation in Microsoft PowerShell allows an authorized attacker to elevate privileges locally.
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 vulnerability in Microsoft PowerShell involves improper input validation that can be exploited by an authorized attacker to achieve local privilege escalation. The issue stems from the way PowerShell handles certain input parameters, allowing a user with baseline access to elevate to higher privileges on the local 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< 10.0.14393.9060< 10.0.17763.8644< 10.0.19044.7184< 10.0.19045.7184< 10.0.22631.6936< 10.0.26100.8246< 10.0.26200.8246< 10.0.28000.1836CVSS 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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Check Windows build versionRun 'winver' or 'systeminfo | findstr /B /C:"OS Version"' to obtain the build numberAffected if The build number falls below the affected threshold for your Windows release (e.g., < 10.0.14393.9060 for Windows 10 1607, < 10.0.17763.8644 for Windows 10 1809, etc.)
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Verify PowerShell versionRun '$PSVersionTable.PSVersion' in PowerShell to get the installed versionAffected if The PowerShell version corresponds to a Windows build that is below the affected thresholds listed for your Windows release
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Confirm local user access scopeRun 'net user' or check Local Users and Groups (lusrmgr.msc) to enumerate local accountsAffected if Untrusted or low-privilege local users exist on the system who could potentially exploit the input validation flaw
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Audit PowerShell script execution policyRun 'Get-ExecutionPolicy -List' to review execution policies for various scopesAffected if Execution policy permits running scripts that could deliver malicious input to the vulnerable parameter handler
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Review PowerShell module loggingCheck Windows Event Viewer under Application and Services Logs > Windows PowerShell for script block logging statusAffected if Module logging is not enabled, as this limits visibility into potential exploitation attempts via the input validation flaw
You are affected if your Windows build number is below the threshold for your specific Windows release and you have untrusted local users with baseline access.
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 · scoped10.0.14393.906010.0.17763.864410.0.19044.7184
Apply Microsoft security updates for PowerShell as they become available, prioritizing systems where untrusted users have local access. Until a patch is released, restrict local access to trusted users only and monitor for unusual PowerShell execution patterns.
Upgrade to the build number at or above: Windows 10 1607 to 10.0.14393.9060 | Windows 10 1809 to 10.0.17763.8644 | Windows 10 21h2 to 10.0.19044.7184 | Windows 10 22h2 to 10.0.19045.7184 | Windows 11 23h2 to 10.0.22631.6936 | Windows 11 24h2 to 10.0.26100.8246 | Windows 11 25h2 to 10.0.26200.8246 |
- 1. Identify the current Windows version by running 'winver' or 'systeminfo' in Command Prompt
- 2. Determine which Windows release channel you are on (e.g., Windows 10 22h2, Windows 11 23h2, etc.)
- 3. For Windows 10: Navigate to Settings > Update & Security > Windows Update and install all available updates
- 4. For Windows 11: Navigate to Settings > Windows Update and install all available updates
- 5. Alternatively, manually download and install the specific security update from Microsoft Update Catalog matching your Windows version
- 6. After installation, restart the computer to apply changes
- 7. Verify the update was successful by checking the installed KB article or running 'winver' to confirm the build number matches or exceeds the fixed version
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 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 $1,936.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-26170 — 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-2026-26170 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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