CVE-2026-88196

Summary

A heap-based buffer overflow in Microsoft Office allows remote code execution when a user opens a specially crafted document over a network. This vulnerability affects multiple Microsoft 365 and Office versions, making it particularly dangerous for enterprise environments where users frequently open documents from shared locations or email attachments.

Exploitability

Exploitation requires a user to open a malicious document, typically via email attachment or network share, with minimal preconditions beyond having Microsoft Office installed and accessible over the network.

Blast radius

If exploited, this vulnerability could allow attackers to execute arbitrary code on affected systems with the privileges of the logged-in user, potentially leading to full system compromise and lateral movement across the enterprise network.

Detection

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

Prioritized remediation

Deploy the Microsoft Office update KB5042891 for Office 2021 and Office 2024, or install the latest cumulative update for Microsoft 365 Apps for enterprise.

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