dbcve.org
Windows 10 1809Operating system · Microsoft

CVE-2026-20829

MEDIUM · 5.5 CVSS v3.1 Published 2026-01-13
Fix available
A fix is available. Upgrade to 10.0.17763.8276 / 10.0.19044.6809 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click

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 · unedited
Out-of-bounds read in Windows TPM allows an authorized attacker to disclose information locally.

In the news

Third-party coverage
Trending covered by 1 outlet this week · latest 7mo ago

Surfaced from public web coverage — external links open in a new tab.

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 confidence

An out-of-bounds read vulnerability in Windows Trusted Platform Module (TPM) enables a local, authorized attacker to read memory beyond intended boundaries, potentially exposing sensitive information.

MitigationApply available Windows security updates and verify TPM firmware is current. Prioritize patching systems with elevated privileges or access to sensitive data.

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
Windows 10 1809Operating system
Affected:< 10.0.17763.8276
Windows 10 21h2Operating system
Affected:< 10.0.19044.6809
Windows 10 22h2Operating system
Affected:< 10.0.19045.6809
Windows 11 23h2Operating system
Affected:< 10.0.22631.6491
Windows 11 24h2Operating system
Affected:< 10.0.26100.7623
Windows 11 25h2Operating system
Affected:< 10.0.26200.7623
Windows Server 2019Operating system
Affected:< 10.0.17763.8276
Windows Server 2022Operating system
Affected:< 10.0.20348.4648

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

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 checks

Work through these to decide whether this CVE applies to you.

  1. Verify TPM is enabled on the system
    Open Device Manager, expand 'Security devices', right-click 'Trusted Platform Module', check Status; or run 'Get-Tpm' in PowerShell and check the 'TpmPresent' and 'TpmReady' properties
    Affected if TPM is not present or not enabled, the system is not affected by this TPM vulnerability
  2. Determine the installed Windows version and build number
    Run 'winver' from Run dialog, or run 'systeminfo' in Command Prompt, or run 'Get-ComputerInfo | Select-Object OsName,OsVersion,OsBuildNumber' in PowerShell
    Affected if The build number is below the threshold for your Windows version (17763.8276 for 10 1809/Server 2019, 19044.6809 for 10 21h2, 19045.6809 for 10 22h2, 22631.6491 for 11 23h2, 26100.7623 for 11 24h2, 26200.7623 for 11 25h2, 20348.4648 for Server 2022)
  3. Confirm the specific Windows edition and build
    Run 'winver' to see the exact Windows release (such as Windows 10 version 22h2 or Windows 11 version 23h2) and the full build number including the KB patch level
    Affected if The displayed build number is less than the corresponding fixed build for that specific Windows release and edition

A system is affected if TPM is enabled and the Windows build number falls below the fixed threshold for its specific Windows release version.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Upgrade available Upgrade to 10.0.17763.8276 / 10.0.19044.6809 / 10.0.19045.6809 or later
Fixed in 10.0.17763.827610.0.19044.680910.0.19045.6809
Interim mitigation

Apply available Windows security updates and verify TPM firmware is current. Prioritize patching systems with elevated privileges or access to sensitive data.

Recommended fix High confidence

Apply Microsoft security updates for Windows 10/11 or Windows Server to reach the minimum fixed build numbers listed above (e.g., 10.0.17763.8276 for Windows 10 1809/Server 2019, 10.0.19044.6809 for Windows 10 21h2, etc.)

  1. Identify the current Windows build version by running 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"'
  2. Ensure Windows Update is enabled: Go to Settings > Update & Security > Windows Update and verify automatic updates are turned on
  3. Manually check for updates by clicking 'Check for updates' in the Windows Update settings
  4. Install all pending security updates, specifically looking for the TPM-related security update
  5. After updates are installed, verify the system has the minimum fixed build: Windows 10 1809/Server 2019 should be >=10.0.17763.8276, Windows 10 21h2 >=10.0.19044.6809, Windows 10 22h2 >=10.0.19045.6809, Windows 11 23h2 >=10.0.22631.6491, Windows 11 24h2 >=10.0.26100.7623, Windows 11 25h2 >=10.0.26200.7623, Windows Server 2022 >=10.0.20348.4648
  6. Restart the system if prompted to complete the update installation
Caveat Standard Windows security update risks apply; ensure backups and system restore points exist before applying patches in production environments

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Windows 10 1809 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,690
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,304.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-20829 in production — separate from our analysis above.

No notes yet

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What this is

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.

What belongs here
  • 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