Windows 10 1507Operating system · Microsoft

CVE-2025-26673

HIGH · 7.5 CVSS v3.1 Published 2025-04-08
Fix available
A fix is available. Upgrade to 10.0.10240.20978 / 10.0.14393.7969 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges 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
Uncontrolled resource consumption in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.

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

This is a denial of service vulnerability in Windows LDAP (Lightweight Directory Access Protocol) stemming from uncontrolled resource consumption. An unauthorized remote attacker can exploit this to exhaust resources on affected Windows systems running LDAP services, causing a denial of service condition.

MitigationApply Microsoft security updates for Windows to patch the LDAP vulnerability, or disable LDAP if not required, and implement network-level rate limiting or segmentation to reduce exposure to unauthenticated attackers.

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 1507Operating system
Affected:< 10.0.10240.20978
Windows 10 1607Operating system
Affected:< 10.0.14393.7969
Windows 10 1809Operating system
Affected:< 10.0.17763.7136
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

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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. Identify the installed Windows build version
    Run 'winver' from the command prompt, or use 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to retrieve the exact Windows build number
    Affected if The build number is lower than the threshold for your Windows release (10.0.10240.20978 for 1507, 10.0.14393.7969 for 1607, 10.0.17763.7136 for 1809, 10.0.19044.5737 for 21h2, 10.0.19045.5737 for 22h2, 10.0.22621.5189 for 11 22h2, 10.0.22631.5189 for 11 23h2, or 10.0.26100.3775 for 11 24h2)
  2. Confirm Windows edition matches affected list
    Check if the system is Windows 10 1507, 1607, 1809, 21h2, 22h2, or Windows 11 22h2, 23h2, or 24h2 using 'winver' or 'systeminfo'
    Affected if The Windows edition and version fall within the affected version ranges listed in the CVE
  3. Verify LDAP service is enabled
    Open Services (services.msc) and look for 'Active Directory Domain Services' or check for LDAP listening ports (389, 636) using 'netstat -an | findstr "389\|636"'
    Affected if LDAP services are running or listening on the system - the vulnerability only applies when LDAP is active
  4. Check for LDAP server role installation
    On servers, use 'Get-WindowsFeature | Where-Object {$_.Name -like "*AD-Domain-Services*"}' in PowerShell to see if Active Directory Domain Services role is installed
    Affected if The AD DS role is installed and the server is functioning as a domain controller or LDAP server

You are affected if your Windows build version is lower than the threshold for your specific Windows release AND LDAP services are running on the system.

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 10.0.10240.20978 / 10.0.14393.7969 / 10.0.17763.7136 or later
Fixed in 10.0.10240.2097810.0.14393.796910.0.17763.7136
Interim mitigation

Apply Microsoft security updates for Windows to patch the LDAP vulnerability, or disable LDAP if not required, and implement network-level rate limiting or segmentation to reduce exposure to unauthenticated attackers.

Recommended fix High confidence

Install the February 2025 Windows Security Update (KBXXXXXX) for your Windows version - the fixed builds are: Windows 10 1507: 10.0.10240.20978+, Windows 10 1607: 10.0.14393.7969+, Windows 10 1809: 10.0.17763.7136+, Windows 10 21h2: 10.0.19044.5737+, Windows 10 22h2: 10.0.19045.5737+, Windows 11 22h

  1. Identify the current Windows version and build number by running 'winver' or 'systeminfo'
  2. Determine which version branch your system is on (e.g., Windows 10 22h2, Windows 11 24h2) from the affected versions list
  3. Apply the Microsoft security update for February 2025 (or the month this CVE was released) that addresses CVE-2025-26673
  4. Verify the update was installed successfully by checking Windows Update history or running 'winver' to confirm the build number meets or exceeds the fixed version for your branch
  5. Restart the system as prompted to complete the update installation
Caveat Standard Windows security update - minimal risk; test in non-production environment before broad deployment to ensure compatibility with line-of-business applications

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

Fix this in Windows 10 1507 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-26673 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-26673 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