Out-of-Bounds Read Vulnerability in Microsoft Office Excel by Microsoft
CVE-2026-26109

8.4HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Apps For Enterprise
Microsoft Excel 2016
Microsoft Office 2019
Microsoft Office Ltsc 2021
Vendor
CVE Published:
10 March 2026

What is CVE-2026-26109?

An out-of-bounds read vulnerability exists in Microsoft Office Excel, allowing unauthorized attackers to execute local code. If successfully exploited, this weakness can compromise the integrity of data and allow for unauthorized actions to be performed within the application.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Excel 2016 32-bit Systems 16.0.0.0 < 16.0.5543.1000

Microsoft Office 2019 32-bit Systems 19.0.0

References

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

CVSS V3.1

Score:
8.4
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.