How severe is CVE-2009-0557?

CVE-2009-0557 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2009-0557 being actively exploited?

Yes. CVE-2009-0557 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-06-08, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2009-0557?

CVE-2009-0557 primarily affects Microsoft Office. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-0557?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2009-0557 have an EU (EUVD) identifier?

Yes. CVE-2009-0557 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2009-0561. It is also flagged as exploited in the EUVD (since 2022-06-08).

When was CVE-2009-0557 published?

CVE-2009-0557 was published on 2009-06-10 and last updated on 2026-06-16.

CVE-2009-0557

CVE-2009-0557 is a high-severity vulnerability in Microsoft Office with a CVSS 3.x base score of 7.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-06-08). The underlying weakness is classified as CWE-94.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 59% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-06-08)
EU (EUVD) id: EUVD-2009-0561
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-06-08)
Weakness: CWE-94
Affected product: Microsoft Office
Published: 2009-06-10
Last modified: 2026-06-16

Description

Excel in Microsoft Office 2000 SP3, Office XP SP3, Office 2003 SP3, and Office 2004 and 2008 for Mac; Excel in 2007 Microsoft Office System SP1 and SP2; Open XML File Format Converter for Mac; Microsoft Office Excel Viewer 2003 SP3; Microsoft Office Excel Viewer; and Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 allow remote attackers to execute arbitrary code via a crafted Excel file with a malformed record object, aka "Object Record Corruption Vulnerability."

Frequently asked questions

What is CVE-2009-0557?: Excel in Microsoft Office 2000 SP3, Office XP SP3, Office 2003 SP3, and Office 2004 and 2008 for Mac; Excel in 2007 Microsoft Office System SP1 and SP2; Open XML File Format Converter for Mac; Microsoft Office Excel Viewer 2003 SP3; Microsoft Office Excel Viewer; and Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 allow remote attackers to execute arbitrary code via a crafted Excel file with a malformed record object, aka "Object Record Corruption Vulnerability."
How severe is CVE-2009-0557?: CVE-2009-0557 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2009-0557 being actively exploited?: Yes. CVE-2009-0557 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-06-08, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2009-0557?: CVE-2009-0557 primarily affects Microsoft Office. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-0557?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2009-0557 have an EU (EUVD) identifier?: Yes. CVE-2009-0557 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2009-0561. It is also flagged as exploited in the EUVD (since 2022-06-08).
When was CVE-2009-0557 published?: CVE-2009-0557 was published on 2009-06-10 and last updated on 2026-06-16.

References

Affected products (14)

cpe:2.3:a:microsoft:office:2000:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2004:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office:2007:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2008:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office:xp:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_compatibility_pack:2007:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_compatibility_pack:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_excel_viewer:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_excel_viewer:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_sharepoint_server:2007:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_sharepoint_server:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:open_xml_file_format_converter:-:*:*:*:*:macos:*:*

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