Heap-based Buffer Overflow in Microsoft Office Excel by Microsoft
CVE-2026-118722

8.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Apps For Enterprise
Microsoft Office 365 For Mac
Microsoft Office Ltsc 2021
Microsoft Office Ltsc 2024
Vendor
CVE Published:
10 November 2026

What is CVE-2026-118722?

A vulnerability exists in Microsoft Office Excel that enables a heap-based buffer overflow, allowing attackers to execute arbitrary code remotely. By crafting a malicious file and exploiting this flaw, an unauthorized entity could gain control over the affected system, leading to potential data breaches and manipulation. It's crucial for users to apply the latest security updates to mitigate the risks associated with this vulnerability.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Office 365 for Mac 1.0.0 < 16.115.26110837

Microsoft Office LTSC 2021 32-bit Systems 16.0.1 < 16.0.14334.21048

References

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

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.