CVE-2026-97777

Summary

A heap-based buffer overflow in Microsoft Excel allows remote attackers to execute arbitrary code when processing malicious Excel files over a network. This vulnerability could enable attackers to gain full control of affected systems.

Exploitability

Exploitation requires a user to open a specially crafted Excel file, making it moderately difficult but achievable through social engineering or phishing campaigns.

Blast radius

If exploited, this vulnerability could affect thousands of users across Microsoft 365 and Office applications, potentially leading to widespread system compromise and data exfiltration.

Detection

No reliable host or network indicator is derivable from the published description.

Prioritized remediation

Deploy the Microsoft Office 2021 version 2408 or later, or Microsoft Office 2024 version 2408 or later, as these versions contain the necessary security fixes for this vulnerability.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.