Internet Information ServerApplication · Microsoft

CVE-2003-0223

MEDIUM · 6.8 CVSS v2.0 Published 2003-06-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
77/100
Remediation priority · High
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
Cross-site scripting vulnerability (XSS) in the ASP function responsible for redirection in Microsoft Internet Information Server (IIS) 4.0, 5.0, and 5.1 allows remote attackers to embed a URL containing script in a redirection message.

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 confidence

Cross-site scripting vulnerability in the ASP redirection function of Microsoft IIS 4.0, 5.0, and 5.1 allows remote attackers to inject malicious script into URLs that get reflected in redirection messages. This is a reflected XSS where the attacker's script is embedded within a redirection URL and executed in the victim's browser.

MitigationApply the relevant Microsoft security patch for this vulnerability (MS03-018 or subsequent updates). For legacy systems running these very old IIS versions, strongly consider upgrading to a supported IIS version or migrating to modern web server platforms.

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
Internet Information ServicesApplication
Affected:= 5.0

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
M
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:M/Au:N/C:P/I:P/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 checks

Work through these to decide whether this CVE applies to you.

  1. Check IIS installation status
    Open Registry Editor and navigate to HKLM\SYSTEM\CurrentControlSet\Services\W3SVC\Parameters. Look for the MajorVersion value to confirm IIS is installed and obtain its version number.
    Affected if MajorVersion does not exist or is missing, indicating IIS is not installed.
  2. Determine installed IIS version
    Read the MajorVersion DWORD value from HKLM\SYSTEM\CurrentControlSet\Services\W3SVC\Parameters. This decimal value represents the IIS version (4 for IIS 4.0, 5 for IIS 5.0/5.1).
    Affected if MajorVersion equals 4 (IIS 4.0) or 5 (IIS 5.0 or 5.1).
  3. Confirm exact IIS 5.x subversion
    Check the Windows version. IIS 5.0 runs on Windows 2000. IIS 5.1 runs on Windows XP Professional. Alternatively, check the file version of w3svc.dll in %systemroot%\system32\inetsrv\.
    Affected if Running Windows 2000 with IIS (version 5) means IIS 5.0; running Windows XP Professional with IIS means IIS 5.1. Both are affected.
  4. Verify ASP is enabled
    Check for the presence of ASP.dll in %systemroot%\system32\inetsrv\ or confirm ASP is allowed in IIS Manager under Web Service Extensions.
    Affected if ASP is installed and enabled, making the ASP redirection function available for exploitation.
  5. Test for reflective URL behavior
    Attempt a request to an ASP page with a redirection parameter containing a test script payload (e.g., /redirect.asp?url=<script>alert(1)</script>) and observe if the script is reflected unsanitized in the response.
    Affected if The script payload is reflected and executed in the browser response, confirming the XSS vulnerability is present.

The environment is affected if IIS version 4.0, 5.0, or 5.1 is installed, ASP is enabled, and crafted redirection URLs can reflect malicious script content in the response.

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 relevant Microsoft security patch for this vulnerability (MS03-018 or subsequent updates). For legacy systems running these very old IIS versions, strongly consider upgrading to a supported IIS version or migrating to modern web server platforms.

Fix this in Internet Information Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2003-0223 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2003-0223 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
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  • Version or environment caveats, and links to real fixes
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