CVE-2026-55141

High

Description

Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

SeverityHigh
CVSS7.8
Exploit probability—
ProductMicrosoft Excel
PublishedJul 14, 2026
First seenJul 14, 2026
Weakness typeCWE-121CWE-121

How to fix

Update
  • microsoft office_online_server16.0.10417.20175 or later

Affected products

ProductAffected versionsFixed in
microsoft excel2016—
microsoft 365_appsNo range specified—
microsoft microsoft_365No range specified—
microsoft office_2019No range specified—
microsoft office_2021No range specified—
microsoft office_2024No range specified—
microsoft office_online_serverv < 16.0.10417.2017516.0.10417.20175

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.