CVE-2011-3403
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 · uneditedMicrosoft Excel 2003 SP3 and Office 2004 for Mac do not properly handle objects in memory, which allows remote attackers to execute arbitrary code via a crafted Excel spreadsheet, aka "Record 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 · moderate confidenceMicrosoft Excel 2003 SP3 and Office 2004 for Mac contain a memory corruption vulnerability when improperly handling objects in memory. Attackers can exploit this by tricking users into opening specially crafted Excel spreadsheets, allowing remote arbitrary code execution with the user's privileges.
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= 2003= 2004CVSS 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
- Complete
- Integrity
- Complete
- Availability
- Complete
AV:N/AC:M/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 checksWork through these to decide whether this CVE applies to you.
-
Check installed Microsoft Excel version on WindowsOpen Excel, go to File > Help, or run 'winword.exe /?' from command line, or check Add/Remove Programs for Microsoft Excel. Look for version number and service pack level.Affected if Version is 2003 with service pack 3 or earlier, or version is unknown but falls at or below 2003
-
Check installed Microsoft Office version on WindowsOpen any Office application, go to File > Help, or check Add/Remove Programs for Microsoft Office. Look for the year-based version (2004, 2003, XP, etc.) and service pack.Affected if Office version is 2003 or earlier, or Office 2004 for Mac is in use
-
Check Microsoft Office for Mac versionOpen any Office for Mac application, go to the application menu and select 'About [Application]'. Look for version number 2004.Affected if Office for Mac version is 2004 (any update level)
-
Verify Excel file preview handler is enabledCheck Windows registry under HKLM\SOFTWARE\Microsoft\Office\Excel\Addins\PreviewPane or look for Excel preview handler DLL files present in system. On affected versions, the preview handler processes Excel files automatically.Affected if Excel preview handler is installed and active (typical default on affected versions)
-
Confirm Excel file association and handler statusCheck file associations for .xls files via 'assoc' command or registry under HKCR\.xls, and verify the Excel executable path points to an affected version.Affected if System opens .xls files with Excel 2003 or earlier version
You are affected if any Windows system has Excel 2003 SP3 or earlier, or any Mac system has Office 2004 for Mac installed, and the Excel file handler is enabled to process spreadsheets.
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 Microsoft security updates MS11-083 which addresses this vulnerability. For systems that cannot be updated, implement workarounds such as blocking Excel files from untrusted sources, disabling the Excel file preview handler, and educating users about not opening unexpected attachments.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2011-3403 — 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-2011-3403 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
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.
- 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