CVE-2026-100209: Microsoft Office Excel Remote Code Execution Vulnerability
Microsoft Office Excel Remote Code Execution Vulnerability
Other sources
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in https://aka.ms/OfficeSecurityReleases - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.17932.21056
Event History
Frequently Asked Questions
Which environments should be prioritized for assessment?
Assess deployments of Microsoft 365 Apps for Enterprise, Microsoft Office Excel, Microsoft Office 365 for Mac, Microsoft Office LTSC for Mac 2024, Microsoft Office LTSC 2024 for 64-bit editions, Microsoft Office LTSC 2024 for 32-bit editions, and Microsoft Office LTSC for Mac 2021.
Does exploitation require attacker privileges or user interaction?
The CVSS vector indicates that an attacker does not need privileges, but user interaction is required. The attack vector is network-based and exploitation complexity is rated low.
What is the expected security impact if exploitation succeeds?
The CVSS impact metrics rate confidentiality, integrity, and availability impact as high. The vulnerability is rated high severity with a CVSS score of 8.8.