CVE-2009-0238
Microsoft Office Remote Code Execution
Microsoft Office
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.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 14 April 2026. US federal agencies were required to remediate it by 28 April 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 42.9%, which is higher than 98.7% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2009-0238 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2009-0238.
What does CVE-2009-0238 affect?
CVE-2009-0238 affects Microsoft Office. 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.
How severe is CVE-2009-0238?
CVE-2009-0238 is rated HIGH with a CVSS base score of 8.8. EPSS puts the probability of exploitation in the next 30 days at 42.9%, higher than 98.7% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 28 April 2026.
How should organisations respond to CVE-2009-0238?
Apply the vendor patch for Microsoft Office as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.