CVE-2026-55131
highpriority · track · 0EPSS 0.005 · 39 %ileDEEUNLRUUSEPSS · scored 2026-10-22
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedMicrosoft 365 Apps for Enterprise for 32-bit Systemsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft 365 Apps for Enterprise for 64-bit Systemsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Excel 2016 (32-bit edition)msrc_csaf
16.0.5561.1001:Security Update:https://support.microsoft.com/help/5002877
https://support.microsoft.com/help/5002877 - FixedMicrosoft Excel 2016 (64-bit edition)msrc_csaf
16.0.5561.1001:Security Update:https://support.microsoft.com/help/5002877
https://support.microsoft.com/help/5002877 - FixedMicrosoft Office 2019 for 32-bit editionsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Office 2019 for 64-bit editionsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Office 365 for Macmsrc_csaf
16.111.26071215:Security Update:https://www.microsoft.com/en-us/microsoft-365/mac/microsoft-365-for-mac?msockid=35f9adb0e74b61392038b90de6fe608c
https://www.microsoft.com/en-us/microsoft-365/mac/microsoft-365-for-mac?msockid=35f9adb0e74b61392038b90de6fe608c - FixedMicrosoft Office LTSC 2021 for 32-bit editionsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Office LTSC 2021 for 64-bit editionsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Office LTSC 2024 for 32-bit editionsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Office LTSC 2024 for 64-bit editionsmsrc_csaf
https://aka.ms/OfficeSecurityReleases:Security Update:https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
https://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates - FixedMicrosoft Office LTSC for Mac 2021msrc_csaf
16.111.26071215:Security Update:https://go.microsoft.com/fwlink/p/?linkid=831049
https://go.microsoft.com/fwlink/p/?linkid=831049 - FixedMicrosoft Office LTSC for Mac 2024msrc_csaf
16.111.26071215:Security Update:https://go.microsoft.com/fwlink/p/?linkid=831049
https://go.microsoft.com/fwlink/p/?linkid=831049 - FixedOffice Online Servermsrc_csaf
16.0.10417.20175:Security Update:https://support.microsoft.com/help/5002884
https://support.microsoft.com/help/5002884
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (93)
Products and version ranges known to be affected.
- Microsoft SharePoint Enterprise Server 2016all versionscert_bundDEcpe:/a:microsoft:sharepoint:enterprise_server_2016
- Microsoft SharePoint Server Subscription Editionall versionscert_bundDEcpe:/a:microsoft:sharepoint:server_subscription_edition
- Microsoft Microsoft 365 Apps for Enterprise16.0.1 → https://aka.ms/OfficeSecurityReleasesenisa_euvdEU
advisories (3)
Vendor and ecosystem advisories describing this.
- NCSC-2026-0237Kwetsbaarheden verholpen in Microsoft OfficeNL2026-07-14csaf · ncsc_nlNL
Microsoft heeft kwetsbaarheden verholpen in diverse Office producten, zoals Word, Excel, Powerpoint en SharePoint.
- WID-SEC-W-2026-2317Microsoft Office Produkte: Mehrere SchwachstellenDeutsch2026-07-14csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in verschiedenen Microsoft Office Produkten ausnutzen, um beliebigen Programmcode auszuführen, um Informationen offenzulegen, um falsche Informationen darzustellen, um seine Privilegien zu erhöhen, und um Sicherheitsvorkehrungen zu umgehen.
- msrc_CVE-2026-55131Microsoft Excel Remote Code Execution Vulnerability2026-07-14csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (3)
External citations — patches, advisories, analysis.
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan