CVE-2000-1227
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 · uneditedWindows NT 4.0 and Windows 2000 hosts allow remote attackers to cause a denial of service (unavailable connections) by sending multiple SMB SMBnegprots requests but not reading the response that is sent back.
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 · high confidenceWindows NT 4.0 and Windows 2000 hosts have a vulnerability in their SMB (Server Message Block) implementation. Attackers can cause a denial of service by sending multiple SMBnegprot (negotiation protocol) requests without reading the server's responses, exhausting connection resources and making the server unavailable.
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 dataall versions= 4.0CVSS 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
- Authentication
- None
- Confidentiality
- None
- Integrity
- None
- Availability
- Partial
AV:N/AC:L/Au:N/C:N/I:N/A:P
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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Identify the Windows versionRun 'winver' or check System Properties to view the Windows version. Alternatively, run 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"'Affected if The system is running Windows NT 4.0 or Windows 2000 (any version)
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Confirm SMB service is enabledCheck if the Server service (LanmanServer) is running by opening Services console (services.msc) or running 'net start' and looking for 'Server' or 'Lanman Server'Affected if The SMB/Server service is running and accepting connections
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Verify SMB ports are listeningRun 'netstat -an | findstr "139 445"' to check if ports 139 or 445 are in LISTENING stateAffected if Ports 139 or 445 are open and listening for SMB connections
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Check SMB protocol configurationCheck registry key HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters for SMB version settings, or check the SMB configuration via 'smbstatus' if available on the systemAffected if SMB is configured and accessible on the network
A system is affected if it is running Windows NT 4.0 or Windows 2000 with the SMB/Server service enabled and accessible on the network, making it vulnerable to resource exhaustion from unauthenticated SMBnegprot request floods.
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 dataApply the relevant Microsoft security patch for this vulnerability, or migrate to a supported Windows version as Windows NT 4.0 and Windows 2000 are end-of-life and no longer receive security updates.
- Consultation2.0 h
- Implementation8.0 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 $3,712.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2000-1227 — 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-2000-1227 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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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.
- 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