CVE-2011-0097Excel Vulnerability
Integer underflow in Microsoft Excel 2002 SP3, 2003 SP3, 2007 SP2, and 2010; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Excel Viewer SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2 allows remote attackers to…
Published Apr 13, 2011 · Updated Apr 28, 2026
Key Facts
Patch immediately- CVE-2011-0097 is a critical-severity vulnerability (CVSS 9.3 v2) affecting Excel (Microsoft), Excel Viewer (Microsoft), Office (Microsoft) and 2 more products.
- It is exploited in the wild, listed in Industry KEV feed since Aug 17, 2021. No public exploit code is known.
- EPSS estimates a 32% probability of exploitation in the next 30 days.
- No fixed version is listed yet; check the vendor advisory for mitigations.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Scores
CVSS v2
9.3
AV:N/AC:M/Au:N/C:C/I:C/A:C
EPSS (30-day exploit likelihood)
32%
Higher than 98.2% of all scored CVEs
Exploit maturity
Exploited (KEV)
ATLAS score
55/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Aug 17, 2021
3779 days after publication
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Exploited (KEV)
Public exploit code
0
Proof-of-concept links
In-the-wild evidence
1
Reports of active use
Advisories And Exploit References
- advisory39122
- advisoryhttp://secunia.com/secunia_research/2011-31
- advisoryADV-2011-0940
Description
Integer underflow in Microsoft Excel 2002 SP3, 2003 SP3, 2007 SP2, and 2010; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Excel Viewer SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2 allows remote attackers to execute arbitrary code via a crafted 400h substream in an Excel file, which triggers a stack-based buffer overflow, aka "Excel Integer Overrun Vulnerability."
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Aug 17, 2021 | n/a | Not reported |
Affected Products
10 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ExcelMicrosoft | 2002-sp3, 2003-sp3, 2007-sp2, 2010 | n/a |
| Excel ViewerMicrosoft | See advisory | n/a |
| OfficeMicrosoft | 2004, 2008 | n/a |
| Office Compatibility PackMicrosoft | 2007-sp2 | n/a |
| Open XML File Format ConverterMicrosoft | See advisory | n/a |
Timeline
Publicly disclosed
Apr 13, 2011
Added to Industry KEV feed
Aug 17, 2021
Last updated
Apr 28, 2026
Weakness Type
- CWE-189
References
- advisory39122
- advisorysecunia.com · 2011-31
- advisoryADV-2011-0940
- exploitVulnCheck exploitation report
- other71758
FAQ
Common Questions.
Integer underflow in Microsoft Excel 2002 SP3, 2003 SP3, 2007 SP2, and 2010; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Excel Viewer SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2 allows remote attackers to execute arbitrary code via a crafted 400h s…
Affected: Excel (Microsoft) versions 2002-sp3, 2003-sp3, 2007-sp2, 2010; Excel Viewer (Microsoft); Office (Microsoft) versions 2004, 2008, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Aug 17, 2021.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2011-0097 On Your Attack Surface?
Brandefense matches it against the products discovered on your perimeter and opens a finding the day a CVE like this is listed.
Request A Demo