How severe is CVE-2011-0656?

CVE-2011-0656 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2011-0656 being actively exploited?

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

What products are affected by CVE-2011-0656?

CVE-2011-0656 primarily affects Microsoft Office. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-0656?

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-2011-0656 published?

CVE-2011-0656 was published on 2011-04-13 and last updated on 2026-06-16.

CVE-2011-0656

CVE-2011-0656 is a critical-severity vulnerability in Microsoft Office with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 30% places it in the 98th 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: 30% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Office
Published: 2011-04-13
Last modified: 2026-06-16

Description

Microsoft PowerPoint 2002 SP3, 2003 SP3, 2007 SP2, and 2010; Office 2004, 2008, and 2011 for Mac; Open XML File Format Converter for Mac; Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2; PowerPoint Viewer; PowerPoint Viewer 2007 SP2; and PowerPoint Web App do not properly validate PersistDirectoryEntry records in PowerPoint documents, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a Slide with a malformed record, which triggers an exception and later use of an unspecified method, aka "Persist Directory RCE Vulnerability."

Frequently asked questions

What is CVE-2011-0656?: Microsoft PowerPoint 2002 SP3, 2003 SP3, 2007 SP2, and 2010; Office 2004, 2008, and 2011 for Mac; Open XML File Format Converter for Mac; Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2; PowerPoint Viewer; PowerPoint Viewer 2007 SP2; and PowerPoint Web App do not properly validate PersistDirectoryEntry records in PowerPoint documents, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a Slide with a malformed record, which triggers an exception and later use of an unspecified method, aka "Persist Directory RCE Vulnerability."
How severe is CVE-2011-0656?: CVE-2011-0656 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2011-0656 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 30% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-0656?: CVE-2011-0656 primarily affects Microsoft Office. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-0656?: 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-2011-0656 published?: CVE-2011-0656 was published on 2011-04-13 and last updated on 2026-06-16.

References

Affected products (12)

cpe:2.3:a:microsoft:office:2004:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office:2008:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office:2011:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:office_compatibility_pack:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_powerpoint_viewer:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:open_xml_file_format_converter:*:*:mac:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint:2002:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint:2010:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint_viewer:2007:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint_web_app:*:*:*:*:*:*:*:*

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