CVE-2026-55129: Microsoft Office Remote Code Execution Vulnerability
Published Jul 14, 2026
·Updated
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
Other sources
Microsoft Office Remote Code Execution Vulnerability
— Microsoft
Affected Software
26 affected componentsFixes available
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 365 for Mac<16.111.26071215
16.111.26071215
Microsoft Office LTSC 2024 for 32-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 2016<16.0.5561.1000
16.0.5561.1000
Microsoft Office 2016<16.0.5561.1000
16.0.5561.1000
Microsoft Office LTSC for Mac 2021<16.111.26071215
16.111.26071215
Microsoft Office LTSC 2021 for 64-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC for Mac 2024<16.111.26071215
16.111.26071215
Microsoft 365 Apps for Enterprise<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 32-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps
Microsoft 365 Apps
Microsoft Microsoft 365 Macos
Microsoft Office 2016
Microsoft Office 2016
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
Remediation
Event History
Jul 14, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected 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-2026-55129?
CVE-2026-55129 has a severity rating of high with a score of 7.8.
2
How do I fix CVE-2026-55129?
To fix CVE-2026-55129, you need to apply the relevant security patch released by Microsoft.
3
What type of vulnerability is CVE-2026-55129?
CVE-2026-55129 is a heap-based buffer overflow vulnerability in Microsoft Office.
4
Can CVE-2026-55129 be exploited remotely?
CVE-2026-55129 allows unauthorized attackers to execute code locally on the affected system.
5
Which software versions are affected by CVE-2026-55129?
CVE-2026-55129 affects Microsoft Office 2016, Microsoft 365 Apps for Enterprise, Office 2019, 2021, 2024, and LTSC versions.