CVE-2025-27751: Microsoft Excel Remote Code Execution Vulnerability

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2025-04-08 · updated 2026-08-10
Weakness: CWE-416

Description

Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

Affected products

Microsoft 365 Apps: all versions
Microsoft Excel 2013 Service Pack 1: 2016
Microsoft Office: 2019
Microsoft Office LTSC for Mac 2021: 2021, 2024
Microsoft Office Online Server: all versions
Microsoft 365 Apps: from 16.0.1 before https://aka.ms/OfficeSecurityReleases — fixed in https://aka.ms/OfficeSecurityReleases
Microsoft Excel 2016: from 16.0.0.0 before 16.0.5495.1000 — fixed in 16.0.5495.1000
Microsoft Office LTSC 2021: from 16.0.1 before https://aka.ms/OfficeSecurityReleases — fixed in https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC for Mac 2024: from 16.0.0 before 16.96.25041326 — fixed in 16.96.25041326
Microsoft Office: from 19.0.0 before https://aka.ms/OfficeSecurityReleases — fixed in https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024: from 16.0.0 before https://aka.ms/OfficeSecurityReleases — fixed in https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC for Mac 2021: from 16.0.1 before 16.96.25041326 — fixed in 16.96.25041326
Microsoft Office Online Server: from 16.0.0.0 before 16.0.10417.20003 — fixed in 16.0.10417.20003

How to fix

Upgrade to a fixed version: Microsoft 365 Apps https://aka.ms/OfficeSecurityReleases; Microsoft Excel 2016 16.0.5495.1000; Microsoft Office LTSC 2021 https://aka.ms/OfficeSecurityReleases; Microsoft Office LTSC for Mac 2024 16.96.25041326; Microsoft Office https://aka.ms/OfficeSecurityReleases; Microsoft Office LTSC 2024 https://aka.ms/OfficeSecurityReleases; Microsoft Office LTSC for Mac 2021 16.96.25041326; Microsoft Office Online Server 16.0.10417.20003. Check the vendor advisory for mitigations.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-27751

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