# CVE-2009-3129: Microsoft Excel Featheader Record Memory Corruption Vulnerability

Source: https://junglewise.ai/threats/cve-2009-3129-microsoft-excel-featheader-record-memory-corruption-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2009-3129 · Severity: critical · CVSS 9.3 · Exploited in the wild · Published 2022-03-03

Microsoft Excel is vulnerable to memory corruption when processing a FEATHEADER record with an invalid cbHdrData size element. This flaw affects the pointer offset calculation, allowing remote attackers to execute arbitrary code via a specially crafted spreadsheet.

Technologies: [Microsoft Excel](https://junglewise.ai/threats/technologies/excel). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2009-3129 exploited in the wild?** Yes. CVE-2009-3129 is known to be exploited in the wild, first recorded on 3 March 2022. Treat it as urgent.

**How severe is CVE-2009-3129?** Critical severity, with a CVSS score of 9.3, published 3 March 2022.

**Which products and versions are affected?** Microsoft Excel 2002 SP3, 2003 SP3, 2007 SP1, 2007 SP2; Microsoft Office for Mac 2004, 2008; Microsoft Open XML File Format Converter for Mac; Microsoft Excel Viewer 2003 SP3; and 2 more.

**Is there a fix for CVE-2009-3129?** A patch was published on 2009-11-10. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2009-3129 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2009-3129?** Check whether you run Microsoft Excel. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Excel 2002 SP3, 2003 SP3, 2007 SP1, 2007 SP2
- Microsoft Office for Mac 2004, 2008
- Microsoft Open XML File Format Converter for Mac
- Microsoft Excel Viewer 2003 SP3
- Microsoft Excel Viewer SP1, SP2
- Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1, SP2

## Timeline

- 2009-11-10: advisory: Microsoft Security Bulletin MS09-067 published
- 2009-11-10: patched
- 2022-03-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2022-03-03: disclosed: NVD publication date listed in advisory

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