Stack-Based Buffer Overflow in Microsoft Office Excel by Microsoft
CVE-2026-118720

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-2026-118720?

A stack-based buffer overflow vulnerability in Microsoft Office Excel allows an unauthorized attacker to execute arbitrary code remotely over a network. This vulnerability can be leveraged to manipulate user data and compromise system integrity, making effective mitigation essential. Users are encouraged to apply the necessary security patches provided by Microsoft to protect against potential exploitation.

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

.