| CVE Number | Vulnerability | Product | Severity | Date |
|---|---|---|---|---|
| CVE-2026-20955 | Microsoft Excel Remote Code Execution Vulnerability | Microsoft 365, Microsoft Office | Critical | 29-01-2026 |
Technical Information
An unauthenticated attacker could achieve remote code execution by persuading a user to open a specially crafted malicious file, triggering an untrusted pointer dereference that allows arbitrary code execution locally on the victim system.
Patch release date: Jan 13, 2026
Further information on this vulnerability is available at : CVE-2026-20955
Affected Software
Office Online Server,Microsoft Office 2019 for 32-bit editions,
Microsoft Office 2019 for 64-bit editions,
Microsoft 365 Apps for Enterprise for 32-bit Systems,
Microsoft 365 Apps for Enterprise for 64-bit Systems,
Microsoft Office LTSC for Mac 2021,
Microsoft Office LTSC 2021 for 64-bit editions,
Microsoft Office LTSC 2021 for 32-bit editions,
Microsoft Office LTSC 2024 for 32-bit editions,
Microsoft Office LTSC 2024 for 64-bit editions,
Microsoft Office LTSC for Mac 2024""Office Online Server,
Microsoft Office 2019 for 32-bit editions,
Microsoft Office 2019 for 64-bit editions,
Microsoft 365 Apps for Enterprise for 32-bit Systems,
Microsoft 365 Apps for Enterprise for 64-bit Systems,
Microsoft Office LTSC for Mac 2021,
Microsoft Office LTSC 2021 for 64-bit editions,
Microsoft Office LTSC 2021 for 32-bit editions,
Microsoft Office LTSC 2024 for 32-bit editions,
Microsoft Office LTSC 2024 for 64-bit editions,
Microsoft Office LTSC for Mac 2024