CVE-2026-21709
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 · uneditedA vulnerability allowing a local attacker with administrator privileges to bypass Windows Driver Signature Enforcement.
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 attacker with administrator privileges can bypass Windows Driver Signature Enforcement, a security feature that only allows loading of digitally signed drivers. This allows the attacker to load malicious or vulnerable unsigned drivers, potentially achieving code execution at the kernel level.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:H/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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Confirm Windows operating systemRun 'systeminfo | findstr /B /C:"OS Name"' or check system properties to verify the operating system is Windows-basedAffected if System is not Windows (this vulnerability only affects Windows)
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Check Driver Signature Enforcement statusRun 'bcdedit /enum all' and look for 'driverloadpolicy' setting, or check Registry key HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\ExecuteOptions for 'DLL' value which indicates DSE is disabledAffected if Driver Signature Enforcement is disabled or set to allow unsigned drivers (ExecuteOptions REG_SZ value contains 'DLL')
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Monitor for unsigned driver loading eventsOpen Event Viewer, navigate to Security log, filter for Event ID 219 (Driver loaded) and check the 'Signature Status' field in event details. Also check System log for Event ID 219Affected if Events show drivers loaded with 'Not Signed' or 'Signature Status: Not Signed'
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Review driver loading audit eventsEnable driver load auditing via 'auditpol /set /subcategory:"Driver Load" /success:enable /failure:enable', then review Security Event ID 4656 or 4663 for driver load operationsAffected if Audit logs show successful loads of drivers without valid digital signatures
System is affected if running Windows with Driver Signature Enforcement disabled or bypassed, or if evidence exists of unsigned drivers being loaded onto the system
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 dataRestrict administrator privileges to essential personnel only, apply Microsoft security updates when available, and implement driver blocklisting policies or endpoint detection solutions to monitor for unauthorized driver loading.
- 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-2026-21709 — 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-2026-21709 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
- No spam, self-promotion, credentials, or personal data