dbcve.org
Windows 10 21h2Operating system · Microsoft

CVE-2025-26675

HIGH · 7.8 CVSS v3.1 Published 2025-04-08
Fix available
A fix is available. Upgrade to 10.0.19044.5737 / 10.0.19045.5737 or later.
See remediation →
80/100
Remediation priority · High
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 Subsystem for Linux 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 confidence

A memory safety vulnerability in Windows Subsystem for Linux (WSL) allows an out-of-bounds read operation that can be exploited by a local, authorized attacker to escalate privileges to higher integrity levels. The flaw exists in WSL's handling of certain system calls or memory management, enabling a specially crafted operation to read beyond allocated buffer boundaries.

MitigationApply Microsoft security updates for Windows Subsystem for Linux as they become available through Windows Update. Verify WSL kernel versions and ensure all affected Windows systems receive the cumulative security patches.

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 21h2Operating system
Affected:< 10.0.19044.5737
Windows 10 22h2Operating system
Affected:< 10.0.19045.5737
Windows 11 22h2Operating system
Affected:< 10.0.22621.5189
Windows 11 23h2Operating system
Affected:< 10.0.22631.5189
Windows 11 24h2Operating system
Affected:< 10.0.26100.3775
Windows Server 2022Operating system
Affected:< 10.0.20348.3453
Windows Server 2022 23h2Operating system
Affected:< 10.0.25398.1551
Windows Server 2025Operating system
Affected:< 10.0.26100.3775

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
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 checks

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

  1. Confirm WSL is installed
    Run 'wsl --status' or 'wsl --list' in an elevated command prompt. If the commands fail or show WSL is not available, the system is not using this component.
    Affected if WSL is installed and functional on the system
  2. Check Windows build version
    Run 'winver' or execute 'systeminfo | findstr /C:"Build"' in command prompt. Note the full build number (for example, 10.0.19044.5737).
    Affected if The displayed build number is lower than the threshold for your Windows version
  3. Compare against affected version ranges
    Match your Windows edition and build to these thresholds: Windows 10 21h2 requires 10.0.19044.5737 or higher; Windows 10 22h2 requires 10.0.19045.5737 or higher; Windows 11 22h2 requires 10.0.22621.5189 or higher; Windows 11 23h2 requires 10.0.22631.5189 or higher; Windows 11 24h2 requires 10.0.26100.3775 or higher; Windows Server 2022 requires 10.0.20348.3453 or higher; Windows Server 2022 23h2 requires 10.0.25398.1551 or higher; Windows Server 2025 requires 10.0.26100.3775 or higher.
    Affected if Your installed Windows build is less than the required build number for your specific Windows edition and version

The system is affected if WSL is installed and the Windows build version falls below the minimum build number listed for that specific Windows edition.

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 10.0.19044.5737 / 10.0.19045.5737 / 10.0.20348.3453 or later
Fixed in 10.0.19044.573710.0.19045.573710.0.20348.3453
Interim mitigation

Apply Microsoft security updates for Windows Subsystem for Linux as they become available through Windows Update. Verify WSL kernel versions and ensure all affected Windows systems receive the cumulative security patches.

Recommended fix High confidence

Upgrade to the specified Windows build versions or later via Windows Update - the security patch is delivered through standard Windows cumulative updates

  1. Open Settings > Windows Update and check for available updates
  2. Install all pending Windows updates, which will include the security fix for this vulnerability
  3. After updates are installed, restart your system to complete the remediation
  4. Alternatively, manually verify your Windows build version by running 'winver' and confirm it meets or exceeds the fixed build for your version (19044.5737 for Win10 21h2, 19045.5737 for Win10 22h2, 22621.5189 for Win11 22h2, 22631.5189 for Win11 23h2, 26100.3775 for Win11 24h2/Server2025, 20348.3453 for Server2022, 25398.1551 for Server2022 23h2)
Caveat Standard Windows update risks apply - ensure backups of critical data and verify compatibility with mission-critical applications before applying

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

Fix this in Windows 10 21h2 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
Get the upgrade done

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

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dbcve dependency scanner

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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-2025-26675 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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