Heap-based Buffer Overflow in Microsoft Office Excel
CVE-2026-81947

7.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Apps For Enterprise
Microsoft Excel 2016
Microsoft Office 2016
Microsoft Office 2019
Vendor
CVE Published:
8 September 2026

What is CVE-2026-81947?

A heap-based buffer overflow in Microsoft Office Excel enables attackers to execute arbitrary code on the affected system. This vulnerability can be exploited by an unauthorized user to bypass security mechanisms, potentially leading to severe consequences including data theft or system compromise. Users are advised to apply the latest security updates to mitigate these risks.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1 < 16.0.20326.20138

Microsoft Excel 2016 32-bit Systems 16.0.0.0 < 16.0.5569.1003

Microsoft Office 2016 32-bit Systems 16.0.0 < 16.0.5569.1003

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.