CVE-2026-20957CriticalCVSS 7.8
Microsoft Excel Remote Code Execution Vulnerability
🔗 CVE IDs covered (1)
📋 Description
Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
🎯 Affected products13
- Microsoft 365 Apps for Enterprise for 32-bit Systems
- Microsoft 365 Apps for Enterprise for 64-bit Systems
- Microsoft Excel 2016 (32-bit edition)
- Microsoft Excel 2016 (64-bit edition)
- Microsoft Office 2019 for 32-bit editions
- Microsoft Office 2019 for 64-bit editions
- Microsoft Office LTSC 2021 for 32-bit editions
- Microsoft Office LTSC 2021 for 64-bit editions
- Microsoft Office LTSC 2024 for 32-bit editions
- Microsoft Office LTSC 2024 for 64-bit editions
- Microsoft Office LTSC for Mac 2021
- Microsoft Office LTSC for Mac 2024
- Office Online Server
✅ Remediation
KB5002824 (Security Update) — fixed build 16.0.10417.20083 KBClick to Run (Security Update) — fixed build https://aka.ms/OfficeSecurityReleases KBRelease Notes (Security Update) — fixed build 16.105.26011018 KB5002831 (Security Update) — fixed build 16.0.5535.1000
🔗 References (7)
- advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20957
- patchhttps://www.microsoft.com/en-us/download/details.aspx?id=108522
- referencehttps://support.microsoft.com/help/5002824
- referencehttps://docs.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates
- patchhttps://go.microsoft.com/fwlink/p/?linkid=831049
- patchhttps://www.microsoft.com/en-us/download/details.aspx?id=108521
- referencehttps://support.microsoft.com/help/5002831