CVE-2010-0021
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 · uneditedMultiple race conditions in the SMB implementation in the Server service in Microsoft Windows Vista Gold, SP1, and SP2, Windows Server 2008 Gold, SP2, and R2, and Windows 7 allow remote attackers to cause a denial of service (system hang) via a crafted (1) SMBv1 or (2) SMBv2 Negotiate packet, aka "SMB Memory Corruption Vulnerability."
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 confidenceThis CVE describes race conditions in Microsoft's SMB (Server Message Block) implementation in the Windows Server service. Remote attackers can send crafted SMBv1 or SMBv2 Negotiate packets to trigger memory corruption, causing a denial of service via system hang. The vulnerability affects Windows Vista, Server 2008, and Windows 7.
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 versionsall versionsall versionsall versionsall versionsall versionsCVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:H/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 checksWork through these to decide whether this CVE applies to you.
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Identify Windows versionRun 'winver' or check system properties to determine the exact Windows version and build numberAffected if The version is Windows Vista, Server 2008, Windows 7, Windows XP, Windows 2000, or Windows 2003 Server (all versions of these are affected)
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Verify SMB Server service statusOpen Services console (services.msc) and check if 'Server' (SMB 1.x) or 'SMB 1.x Driver' service is running or set to AutomaticAffected if The SMB Server service is enabled and running on the system
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Check for SMB network listenersRun 'netstat -an | findstr "445 139"' or use PowerShell 'Get-NetTCPConnection -LocalPort 445,139' to see if SMB ports are listeningAffected if Ports 445/TCP or 139/TCP are in LISTENING or ESTABLISHED state, indicating SMB is exposed on the network
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Confirm SMBv1 or SMBv2 is enabledCheck registry key 'HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters' for SMB1 value, or run 'sc.exe query mrxsmb10' to query SMB 1 driver statusAffected if SMBv1 or SMBv2 is enabled and available for negotiation requests
The system is affected if it runs an affected Windows version AND has SMB (Server service) enabled and accessible on the network, as the vulnerability is triggered by crafted SMB Negotiate packets to exposed SMB services.
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 (MS10-006) to all affected systems. At the network level, block SMB ports (445/TCP and 139/TCP) at the perimeter if external SMB access is not required.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2010-0021 — 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-2010-0021 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
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