CVE-2026-55131: Microsoft Excel Remote Code Execution Vulnerability
Published Jul 14, 2026
·Updated
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Other sources
Microsoft Excel Remote Code Execution Vulnerability
— Microsoft
Affected Software
28 affected componentsFixes available
Microsoft Office LTSC 2024 for 32-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 64-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 32-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 64-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC for Mac 2021<16.111.26071215
16.111.26071215
Microsoft 365 Apps for Enterprise<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Excel 2016<16.0.5561.1001
16.0.5561.1001
Microsoft Office 365 for Mac<16.111.26071215
16.111.26071215
Microsoft Office 2019 for 32-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office Online Server<16.0.10417.20175
16.0.10417.20175
Microsoft Office LTSC for Mac 2024<16.111.26071215
16.111.26071215
Microsoft Excel 2016<16.0.5561.1001
16.0.5561.1001
Microsoft 365 Apps
Microsoft 365 Apps
Microsoft Excel=2016
Microsoft Excel=2016
Microsoft Microsoft 365 Macos
Microsoft Office 2019
Microsoft Office 2019
Microsoft Office 2021
Microsoft Office 2021
Microsoft Office 2021 Macos
Microsoft Office 2024
Microsoft Office 2024
Microsoft Office 2024 Macos
Microsoft Office Online Server<16.0.10417.20175
Remediation
Event History
Jul 14, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
Updated
via Microsoft·02:00 PM
Affected Software
CVE Published
via MITRE·05:08 PM
Data Sourced
via MITRE·05:08 PM
DescriptionSeverity
Data Sourced
via NVD·06:18 PM
RemedyDescriptionSeverityWeaknessAffected Software
Frequently Asked Questions
1
What is the severity of CVE-2026-55131?
The severity of CVE-2026-55131 is high with a score of 7.8.
2
How do I fix CVE-2026-55131?
CVE-2026-55131 can be fixed by applying the latest security patch provided by Microsoft.
3
What type of vulnerability is CVE-2026-55131?
CVE-2026-55131 is a heap-based buffer overflow vulnerability.
4
What are the potential impacts of CVE-2026-55131?
CVE-2026-55131 allows an unauthorized attacker to execute code locally if exploited.
5
Which products are affected by CVE-2026-55131?
CVE-2026-55131 affects Microsoft 365 Apps for Enterprise, Microsoft Excel 2016, Microsoft Office Online Server, Microsoft Office 2019, Microsoft Office 2021, and Microsoft Office 2024.