OutlookApplication · Microsoft

CVE-2006-2055

MEDIUM · 5.0 CVSS v2.0 Published 2006-04-26
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
Argument injection vulnerability in Microsoft Outlook 2003 SP1 allows user-assisted remote attackers to modify command line arguments to an invoked mail client via " (double quote) characters in a mailto: scheme handler, as demonstrated by launching Microsoft Outlook with an arbitrary filename as an attachment. NOTE: it is not clear whether this issue is implementation-specific or a problem in the Microsoft API.

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

Argument injection vulnerability in Microsoft Outlook 2003 SP1 mailto: scheme handler allows remote attackers to inject or modify command line arguments via double quote characters in mailto: URLs, potentially launching Outlook with arbitrary filenames as attachments.

MitigationUpgrade to a supported version of Microsoft Outlook or apply available Microsoft security patches; exercise caution with mailto: links from untrusted sources.

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
OutlookApplication
Affected:= 2003

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. Verify Microsoft Outlook 2003 is installed
    Open Outlook and go to Help > About Microsoft Outlook, or check the Windows registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\11.0\Outlook\InstallRoot to confirm version 2003
    Affected if The installed version is Microsoft Outlook 2003 (version 11.x)
  2. Confirm mailto: protocol handler is registered
    Check Windows registry for the mailto: handler at HKEY_CLASSES_ROOT\mailto\shell\open\command
    Affected if The mailto: protocol handler entry exists in the Windows registry and points to the Outlook executable
  3. Verify Outlook is configured as default mail client
    Check if Outlook is set as the default mail handler in Windows Control Panel > Default Programs > Set Associations, or attempt to open a mailto: link and observe if Outlook launches
    Affected if Outlook is registered as the default handler for mailto: URLs in the Windows system
  4. Check for Outlook security update KB911801
    Open Windows Update or check Add/Remove Programs for installed updates; look for security update KB911801 or later
    Affected if Security update KB911801 is NOT installed, indicating the vulnerability patch is missing

The environment is affected if Microsoft Outlook 2003 is installed with the mailto: scheme handler enabled and the security patch KB911801 has not been applied.

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

Upgrade to a supported version of Microsoft Outlook or apply available Microsoft security patches; exercise caution with mailto: links from untrusted sources.

Fix this in Outlook 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
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2006-2055 — 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-2006-2055 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