How severe is CVE-2011-1276?

CVE-2011-1276 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2011-1276 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 28% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-1276?

CVE-2011-1276 primarily affects Microsoft Excel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-1276?

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-2011-1276 published?

CVE-2011-1276 was published on 2011-06-16 and last updated on 2026-06-16.

CVE-2011-1276

CVE-2011-1276 is a critical-severity vulnerability in Microsoft Excel with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 28% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 28% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Microsoft Excel
Published: 2011-06-16
Last modified: 2026-06-16

Description

Buffer overflow in Microsoft Excel 2002 SP3, 2003 SP3, and 2007 SP2; 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 or cause a denial of service (memory corruption) via a crafted Excel spreadsheet, related to improper validation of record information, aka "Excel Buffer Overrun Vulnerability."

Frequently asked questions

What is CVE-2011-1276?: Buffer overflow in Microsoft Excel 2002 SP3, 2003 SP3, and 2007 SP2; 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 or cause a denial of service (memory corruption) via a crafted Excel spreadsheet, related to improper validation of record information, aka "Excel Buffer Overrun Vulnerability."
How severe is CVE-2011-1276?: CVE-2011-1276 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2011-1276 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 28% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-1276?: CVE-2011-1276 primarily affects Microsoft Excel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-1276?: 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-2011-1276 published?: CVE-2011-1276 was published on 2011-06-16 and last updated on 2026-06-16.

References

Affected products (8)

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

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