CVE-2026-102855

Summary

A heap-based buffer overflow in Microsoft Office Visio allows remote attackers to execute arbitrary code when processing malicious Visio 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 convince a user to open a specially crafted Visio file, though the attack can be delivered via network share or email attachment with minimal user interaction required.

Blast radius

The impact could be significant as Visio is commonly used in business environments for diagramming and technical documentation, potentially allowing attackers to gain full system access on vulnerable machines.

Detection

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

Prioritized remediation

Deploy Microsoft Security Update KB5042798 immediately, which addresses this vulnerability in Visio 2016, Visio 2019, and Visio 2021.

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