How severe is CVE-2011-1989?

CVE-2011-1989 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2011-1989 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 21% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-1989?

CVE-2011-1989 primarily affects Microsoft Excel. In total, 23 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-1989?

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-2011-1989 published?

CVE-2011-1989 was published on 2011-09-15 and last updated on 2026-06-16.

CVE-2011-1989

CVE-2011-1989 is a critical-severity vulnerability in Microsoft Excel with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 21% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 21% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Excel
Published: 2011-09-15
Last modified: 2026-06-16

Description

Microsoft Excel 2003 SP3 and 2007 SP2; Excel in Office 2007 SP2; Excel 2010 Gold and SP1; Excel in Office 2010 Gold and SP1; Office 2004, 2008, and 2011 for Mac; Open XML File Format Converter for Mac; Excel Viewer SP2; Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2; Excel Services on Office SharePoint Server 2007 SP2; Excel Services on Office SharePoint Server 2010 Gold and SP1; and Excel Web App 2010 Gold and SP1 do not properly parse conditional expressions associated with formatting requirements, which allows remote attackers to execute arbitrary code via a crafted spreadsheet, aka "Excel Conditional Expression Parsing Vulnerability."

Frequently asked questions

What is CVE-2011-1989?: Microsoft Excel 2003 SP3 and 2007 SP2; Excel in Office 2007 SP2; Excel 2010 Gold and SP1; Excel in Office 2010 Gold and SP1; Office 2004, 2008, and 2011 for Mac; Open XML File Format Converter for Mac; Excel Viewer SP2; Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2; Excel Services on Office SharePoint Server 2007 SP2; Excel Services on Office SharePoint Server 2010 Gold and SP1; and Excel Web App 2010 Gold and SP1 do not properly parse conditional expressions associated with formatting requirements, which allows remote attackers to execute arbitrary code via a crafted spreadsheet, aka "Excel Conditional Expression Parsing Vulnerability."
How severe is CVE-2011-1989?: CVE-2011-1989 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2011-1989 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 21% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-1989?: CVE-2011-1989 primarily affects Microsoft Excel. In total, 23 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-1989?: 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-2011-1989 published?: CVE-2011-1989 was published on 2011-09-15 and last updated on 2026-06-16.

References

Affected products (23)

cpe:2.3:a:microsoft:excel:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2010:*:x32:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2010:*:x64:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2010:sp1:x32:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2010:sp1:x64:*:*:*:*:*
cpe:2.3:a:microsoft:excel_viewer:*:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel_web_app:2010:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel_web_app:2010:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2004:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2008:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office:2010:*:x32:*:*:*:*:*
cpe:2.3:a:microsoft:office:2010:*:x64:*:*:*:*:*
cpe:2.3:a:microsoft:office:2010:sp1:x32:*:*:*:*:*
cpe:2.3:a:microsoft:office:2010:sp1:x64:*:*:*:*:*
cpe:2.3:a:microsoft:office:2011:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office_compatibility_pack:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:open_xml_file_format_converter:*:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2007:sp2:x32:*:*:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2007:sp2:x64:*:*:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2010:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2010:sp1:*:*:*:*:*:*

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