Internet Information ServerApplication · Microsoft

CVE-1999-1376

HIGH · 10.0 CVSS v2.0 Published 1999-01-14
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
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
Buffer overflow in fpcount.exe in IIS 4.0 with FrontPage Server Extensions allows remote attackers to execute arbitrary commands.

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

Buffer overflow vulnerability in fpcount.exe, a FrontPage hit counter component included with FrontPage Server Extensions on IIS 4.0. The overflow allows remote attackers to execute arbitrary commands by sending specially crafted input to the vulnerable executable.

MitigationRemove or disable the fpcount.exe component from IIS 4.0, apply Microsoft's security patches for FrontPage Server Extensions, or migrate to supported IIS versions with current FrontPage extensions.

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
Internet Information ServerApplication
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
Complete
Integrity
Complete
Availability
Complete

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

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. Check IIS version
    Open IIS Manager, right-click on the server, select Properties, and check the version under 'Internet Information Services' or run 'iisreset' /status or check the Windows version and IIS installation
    Affected if The system is running IIS version 4.0 specifically. Earlier versions (IIS 3.0) or later versions (IIS 5.0+) are not affected by this specific CVE.
  2. Locate fpcount.exe
    Search for fpcount.exe in the web root directories and Scripts folders. Typical paths include C:\Inetpub\Scripts\fpcount.exe or C:\Program Files\Common Files\Microsoft Shared\web server extensions\...\fpcount.exe
    Affected if fpcount.exe exists on the server. If it does not exist, the vulnerability cannot be exploited.
  3. Check if FrontPage Server Extensions are installed
    Look for the FrontPage Server Extensions installation directories (webext5.dll, fpsrvadm.exe, or check Add/Remove Programs for Microsoft FrontPage Server Extensions)
    Affected if FrontPage Server Extensions are installed. The vulnerability is present in the fpcount.exe component bundled with these extensions on IIS 4.0.
  4. Verify fpcount.exe is accessible via web
    Attempt to access fpcount.exe through a browser (e.g., http://yourserver/scripts/fpcount.exe or check IIS script mappings for .exe extensions). Check IIS Manager under 'Home Directory' > 'Configuration' > 'App Mappings'
    Affected if The executable is mapped in IIS script mappings and reachable via HTTP/HTTPS. Without web accessibility, remote exploitation is not possible.

A system is affected only if it runs IIS 4.0 with FrontPage Server Extensions installed and fpcount.exe present and accessible via the web server.

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

Remove or disable the fpcount.exe component from IIS 4.0, apply Microsoft's security patches for FrontPage Server Extensions, or migrate to supported IIS versions with current FrontPage extensions.

Fix this in Internet Information Server Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,820
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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-1999-1376 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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data