CVE-2026-97763

Summary

A heap-based buffer overflow in Microsoft Office Excel allows remote attackers to execute arbitrary code when processing malicious Excel files. This vulnerability is particularly dangerous because it can be triggered over a network without user interaction, making it ideal for remote exploitation.

Exploitability

Exploitation is moderately difficult and requires an attacker to deliver a specially crafted Excel file to a target system, but the attack can be executed remotely with no user interaction once the file is opened.

Blast radius

The vulnerability affects all Microsoft 365 apps, Office 2021, Office 2024, and Office Online Server, potentially impacting thousands of users across an organization when exploited.

Detection

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

Prioritized remediation

Deploy the Microsoft Security Update KB5049327 immediately to protect against this vulnerability.

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