How severe is CVE-2009-3131?

CVE-2009-3131 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-3131 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-3131?

CVE-2009-3131 primarily affects Microsoft Compatibility Pack Word Excel Powerpoint. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-3131?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2009-3131 published?

CVE-2009-3131 was published on 2009-11-11 and last updated on 2026-06-16.

CVE-2009-3131

CVE-2009-3131 is a critical-severity vulnerability in Microsoft Compatibility Pack Word Excel Powerpoint with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 25% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-94.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 25% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Microsoft Compatibility Pack Word Excel Powerpoint
Published: 2009-11-11
Last modified: 2026-06-16

Description

Microsoft Office Excel 2002 SP3, 2003 SP3, and 2007 SP1 and SP2; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Office Excel Viewer 2003 SP3; Office Excel Viewer SP1 and SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 allow remote attackers to execute arbitrary code via a spreadsheet with a crafted formula embedded in a cell, aka "Excel Formula Parsing Memory Corruption Vulnerability."

Frequently asked questions

What is CVE-2009-3131?: Microsoft Office Excel 2002 SP3, 2003 SP3, and 2007 SP1 and SP2; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Office Excel Viewer 2003 SP3; Office Excel Viewer SP1 and SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 allow remote attackers to execute arbitrary code via a spreadsheet with a crafted formula embedded in a cell, aka "Excel Formula Parsing Memory Corruption Vulnerability."
How severe is CVE-2009-3131?: CVE-2009-3131 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-3131 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-3131?: CVE-2009-3131 primarily affects Microsoft Compatibility Pack Word Excel Powerpoint. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-3131?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2009-3131 published?: CVE-2009-3131 was published on 2009-11-11 and last updated on 2026-06-16.

References

Affected products (12)

cpe:2.3:a:microsoft:compatibility_pack_word_excel_powerpoint:2007:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:compatibility_pack_word_excel_powerpoint:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2002:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2007:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel_viewer:*:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel_viewer:*:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel_viewer:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2004:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office:2008:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:open_xml_file_format_converter:*:*:mac:*:*:*:*:*

More vulnerabilities in Microsoft Compatibility Pack Word Excel Powerpoint

CVE-2009-3134 — Critical (CVSS 9.3): Microsoft Office Excel 2002 SP3, 2003 SP3, and 2007 SP1 and SP2; Office 2004 and 2008 for Mac; Open XML File Format…
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CVE-2009-3127 — Critical (CVSS 9.3): Microsoft Office Excel 2002 SP3 and 2003 SP3, Office 2004 and 2008 for Mac, Open XML File Format Converter for Mac, and…

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