Microsoft Office Remote Code Execution
Microsoft / Office
Microsoft Office Excel contains a remote code execution vulnerability that could allow an attacker to take complete control of an affected system if a user opens a specially crafted Excel file that includes a malformed object.
- CVE identifier
- CVE-2009-0238
- Added to KEV
- Apr 14, 2026
- CISA catalog dueDate
- Apr 28, 2026
The dates above are catalog fields. The addition date does not establish when the vulnerability was discovered or first exploited. Confirm which requirements apply to your organisation separately.
Publisher's 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.
This wording is attributed to the CISA snapshot. Verify current vendor guidance, affected versions and your deployment before applying changes.
Keep the signals separate.
- Ransomware use, as reported by CISA
- Unknown
- CVSS severity
- Not supplied by KEV
- EPSS probability
- Not available
No EPSS value was supplied for this record in the current snapshot. Unknown values are not treated as zero.
“Unknown” ransomware use is an unknown source field, not proof that ransomware activity has not occurred.
Source notes
https://learn.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-009 ; https://nvd.nist.gov/vuln/detail/CVE-2009-0238
Source & freshness
Source updated: Nov 6, 2026, 7:44 PM UTC
Successfully checked: Nov 8, 2026, 12:22 AM UTC
This snapshot is older than 36 hours. Check current publisher guidance.
Automated source record, not an editorial advisory or an independent discovery. No affected or fixed version is inferred, and no organisation-specific risk rating is generated.