What is CVE-2009-0238?

CVE-2009-0238 is a high-severity vulnerability in Microsoft Excel, classified under Code Injection. CVSS score: 8.8/10. Published 2009-02-25.

How severe is CVE-2009-0238?

High severity. CVSS v3 base score is 8.8 out of 10.

Is CVE-2009-0238 known to be exploited?

Yes. CVE-2009-0238 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-04-14), indicating it is being actively exploited.

RCE in Microsoft Excel

CVE-2009-0238

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.

Vulnerability class: RCE (Remote Code Execution)

Published 2009-02-25 · last modified 2026-06-16.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.429 (98.7th percentile), scored 2026-10-18.

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 99th percentile — 98.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.432 · newest: 0.429 · change: -0.003

Affected products

Microsoft Excel — versions 2000, 2002, 2003
Microsoft Excel Viewer
Microsoft Office — versions 2004, 2008
Microsoft Office Compatibility Pack — versions 2007
Microsoft Office Excel Viewer — versions 2003

Weakness classification (CWE)

CWE-94 — Code Injection

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2026-04-14. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2026-04-28.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

References

www.microsoft.com/technet/security/advisory/968272.mspx (Vendor Advisory)
www.vupen.com/english/advisories/2009/1023 (vdb-entry, Broken Link)
exchange.xforce.ibmcloud.com/vulnerabilities/48875 (Third Party Advisory, vdb-entry)
www.us-cert.gov/cas/techalerts/TA09-104A.html (US Government Resource, third-party-advisory)
www.securityfocus.com/bid/33870 (vdb-entry, Broken Link)
www.symantec.com/business/security_response/writeup.jsp (Broken Link)
docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-009 (vendor-advisory, Vendor Advisory)
oval.cisecurity.org/repository/search/definition/oval:org.mitre.oval:def:5968 (Broken Link, signature, vdb-entry)
isc.sans.org/diary.html (Press/Media Coverage)
securitytracker.com/id (vdb-entry, Broken Link)

Frequently asked questions

What is CVE-2009-0238?: CVE-2009-0238 is a high-severity vulnerability in Microsoft Excel, classified under Code Injection. CVSS score: 8.8/10. Published 2009-02-25.
How severe is CVE-2009-0238?: High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2009-0238 known to be exploited?: Yes. CVE-2009-0238 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-04-14), indicating it is being actively exploited.