---
id: "CVE-2009-0238"
kind: "vulnerability"
aliases: ["CVE-2009-0238"]
title: "Microsoft Office Excel 2000 SP3, 2002 SP3, 2003 SP3, and 2007 SP1; Excel Viewer 2003 Gold and SP3; Excel Viewer;\u2026"
severity: "critical"
cvss: 9.3
epss: null
exploited: true
status: "open"
category: "package"
products: [{"name": "Microsoft Office", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft excel", "fixed": [], "affected": "= 2000", "ecosystem": "vendor"}, {"name": "microsoft excel", "fixed": [], "affected": "= 2002", "ecosystem": "vendor"}, {"name": "microsoft excel", "fixed": [], "affected": "= 2003", "ecosystem": "vendor"}, {"name": "microsoft excel", "fixed": [], "affected": "= 2007", "ecosystem": "vendor"}, {"name": "microsoft excel viewer", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft office", "fixed": [], "affected": "= 2004", "ecosystem": "vendor"}, {"name": "microsoft office", "fixed": [], "affected": "= 2008", "ecosystem": "vendor"}, {"name": "microsoft office compatibility pack", "fixed": [], "affected": "= 2007", "ecosystem": "vendor"}, {"name": "microsoft office excel viewer", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft office excel viewer", "fixed": [], "affected": "= 2003", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["excel", "exploited", "microsoft-office", "package", "windows"]
not_affected_if: ["no-office-installed"]
published_at: "2009-02-25T16:30:00+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2009-0238", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2009-0238", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# Microsoft Office Excel 2000 SP3, 2002 SP3, 2003 SP3, and 2007 SP1; Excel Viewer 2003 Gold and SP3; Excel Viewer;…

Microsoft Excel has a remote code execution bug triggered by opening a specially crafted file containing a malformed object. An attacker who gets a user to open the file can take full control of the machine, and CISA lists it as actively exploited.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Microsoft Office affected ? fixed ?
- vendor:microsoft excel affected = 2000 fixed ?
- vendor:microsoft excel affected = 2002 fixed ?
- vendor:microsoft excel affected = 2003 fixed ?
- vendor:microsoft excel affected = 2007 fixed ?
- vendor:microsoft excel viewer affected ? fixed ?
- vendor:microsoft office affected = 2004 fixed ?
- vendor:microsoft office affected = 2008 fixed ?
- vendor:microsoft office compatibility pack affected = 2007 fixed ?
- vendor:microsoft office excel viewer affected ? fixed ?
- vendor:microsoft office excel viewer affected = 2003 fixed ?

## Fix

Apply the vendor mitigations and patches referenced by CISA for Microsoft Office; the sources do not name the specific patch or version.
If no mitigation is available, discontinue use of the affected product per CISA guidance.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2009-0238
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2009-0238

## From the sources

Microsoft Office Excel 2000 SP3, 2002 SP3, 2003 SP3, and 2007 SP1; Excel Viewer 2003 Gold and SP3; Excel Viewer; Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1; and Excel in Microsoft Office 2004 and 2008 for Mac allow remote attackers to execute arbitrary code via a crafted Excel document that triggers an access attempt on an invalid object, as exploited in the wild in February 2009 by Trojan.Mdropper.AC.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_