Remote Code Execution Flaw in Microsoft Office Excel
CVE-2026-97778

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:
13 October 2026

What is CVE-2026-97778?

A vulnerability in Microsoft Office Excel allows an unauthorized attacker to execute arbitrary code by exploiting an integer overflow issue. This flaw could enable attackers to compromise systems over a network, posing significant risks to users who utilize affected versions of Excel. Users are encouraged to apply the necessary patches to safeguard against potential threats.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Office 365 for Mac 1.0.0 < 16.114.26101123

Microsoft Office LTSC 2021 32-bit Systems 16.0.1 < 16.0.14334.20974

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

.