CVE-2025-26670
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 · uneditedUse after free in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to execute code 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 confidenceUse-after-free vulnerability in Windows LDAP (Lightweight Directory Access Protocol) implementation that allows an unauthenticated remote attacker to execute arbitrary code via specially crafted LDAP network requests.
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< 10.0.10240.20978< 10.0.14393.7969< 10.0.17763.7136< 10.0.19044.5737< 10.0.19045.5737< 10.0.22621.5189< 10.0.22631.5189< 10.0.26100.3775CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:H/PR:N/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 versionOpen Command Prompt or PowerShell and run 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to obtain the exact build number. Compare against the affected ranges: Windows 10 1507 requires <10.0.10240.20978, 1607 requires <10.0.14393.7969, 1809 requires <10.0.17763.7136, 21h2 requires <10.0.19044.5737, 22h2 requires <10.0.19045.5737. Windows 11 22h2 requires <10.0.22621.5189, 23h2 requires <10.0.22631.5189, 24h2 requires <10.0.26100.3775.Affected if The installed build version falls within any of the affected version ranges listed.
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Verify LDAP client service statusOpen Services (services.msc) and locate 'LDAP Client' or run 'Get-Service -Name LDAP*' in PowerShell. Check if the service exists and its current status (Running, Stopped, Disabled).Affected if The LDAP Client service is present and enabled on the system.
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Check for Active Directory Domain Services roleOpen Server Manager (on servers) or run 'Get-WindowsFeature AD-Domain-Services' in PowerShell (Server), or check 'System Information' > 'OS Configuration' for Domain membership. On client Windows, check System Properties for Domain/workgroup info.Affected if The system is joined to an Active Directory domain or has AD DS server role installed.
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Inspect LDAP network listening portsOpen Command Prompt and run 'netstat -an | findstr "389\|636"' to check if LDAP ports (389 for LDAP, 636 for LDAPS) are listening on network interfaces. Use 'netsh advfirewall firewall show rule name=all' to verify firewall rules permitting LDAP traffic.Affected if The system is listening on LDAP ports 389/636 on a network-facing adapter, indicating exposure to network LDAP requests.
A system is affected if it runs a Windows version within the affected build ranges AND has LDAP client functionality enabled or Active Directory integration present, with network exposure to LDAP ports.
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 · scoped10.0.10240.2097810.0.14393.796910.0.17763.7136
Apply Microsoft security patches for CVE-2025-26670 as they become available through Windows Update, and verify LDAP service functionality and Active Directory integration post-patch.
Install the appropriate Microsoft security update for your Windows version from Windows Update or the Microsoft Update Catalog - minimum fixed versions range from 10.0.10240.20978 (Win10 1507) to 10.0.26100.3775 (Win11 24h2) depending on your OS version
- Open Windows Update by pressing Windows Key + I, then navigate to Update & Security > Windows Update
- Click 'Check for updates' to scan for available updates
- Install any available security updates, particularly the cumulative update for your Windows version
- After installation, restart your computer to apply the changes
- Alternatively, manually download and install the specific security update from the Microsoft Update Catalog matching your Windows version (e.g., for Windows 10 22h2, install the update containing version 10.0.19045.5737 or later)
- Verify the update was installed successfully by checking Windows Update history
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation4.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,504.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-26670 — 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-2025-26670 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