Windows 2000Operating system · Microsoft

CVE-2005-2150

MEDIUM · 5.0 CVSS v2.0 Published 2005-07-11
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
59/100
Remediation priority · Elevated
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
Windows NT 4.0 and Windows 2000 before URP1 for Windows 2000 SP4 does not properly prevent NULL sessions from accessing certain alternate named pipes, which allows remote attackers to (1) list Windows services via svcctl or (2) read eventlogs via eventlog.

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 confidence

Windows NT 4.0 and Windows 2000 before the Update Rollup Package 1 for SP4 fail to properly restrict NULL sessions (unauthenticated remote connections) from accessing certain named pipes, specifically svcctl (Service Control Manager) and eventlog. This allows remote attackers to enumerate Windows services and read event log contents without any authentication.

MitigationApply the Windows 2000 Update Rollup Package 1 (URP1) for SP4, or for systems where patching is not possible, configure registry restrictions to block NULL session access to named pipes.

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 2000Operating system
Affected:all versions
Windows NtOperating system
Affected:= 4.0

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
Authentication
None
Confidentiality
Partial
Integrity
None
Availability
None

AV:N/AC:L/Au:N/C:P/I:N/A:N

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 Windows version
    Run 'winver' or check System Properties to confirm if the system is Windows 2000 (any version) or Windows NT 4.0.
    Affected if The version is Windows 2000 or Windows NT 4.0.
  2. Check if Update Rollup Package 1 for SP4 is installed
    Open Add/Remove Programs in Control Panel and look for 'Update Rollup Package 1 for SP4' in the list, or check the registry key HKLM\Software\Microsoft\Windows\CurrentVersion\Setup\SP3\Uptodate for Windows 2000 SP4 systems.
    Affected if The system is Windows 2000 without Update Rollup Package 1 for SP4 installed, or is Windows NT 4.0.
  3. Verify NULL session restrictions on the LanmanServer
    Run 'reg query HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters /v RestrictNullSessAccess' and check if the value is set to 1. If the value is missing or set to 0, NULL sessions are not restricted.
    Affected if The RestrictNullSessAccess registry value is missing or set to 0 (NULL sessions allowed).
  4. Check for NULL session access to the svcctl named pipe
    From a remote system or locally, attempt to connect using a NULL session: 'net use \\\\targetname\ipc$ "" /user:""' then verify if the Service Control Manager pipe (\pipe\svcctl) is accessible. This can be checked by examining share access or using tools that enumerate named pipe access.
    Affected if A NULL session can connect and access the svcctl named pipe to enumerate Windows services.

The system is affected if it runs Windows 2000 without Update Rollup Package 1 for SP4 or Windows NT 4.0, and NULL session access to svcctl or eventlog named pipes is not restricted.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the Windows 2000 Update Rollup Package 1 (URP1) for SP4, or for systems where patching is not possible, configure registry restrictions to block NULL session access to named pipes.

Fix this in Windows 2000 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,090
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Scan for this in your stack

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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-2005-2150 in production — separate from our analysis above.

No notes yet

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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
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