Advisoriesby IbisMicrosoftCVE-2026-81959
Microsoft Office Excel: heap buffer overflow
Fix: upgrade to 16.0.20326.20140 or later (6 fixed versions below)
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Microsoft 365 Apps for Enterprise Product | >= 16.0.1, < 16.0.20326.20140 | 16.0.20326.20140 |
| Microsoft Excel 2016 Product | >= 16.0.0.0, < 16.0.5569.1003 | 16.0.5569.1003 |
| Microsoft Office 2016 Product | >= 16.0.0, < 16.0.5569.1003 | 16.0.5569.1003 |
| Microsoft Office 2019 Product | >= 19.0.0, < 16.0.10417.20207 | 16.0.10417.20207 |
| Microsoft Office 365 for Mac Product | >= 1.0.0, < 16.113.26091433 | 16.113.26091433 |
| Microsoft Office LTSC 2021 Product | >= 16.0.1, < 16.0.14334.20906 | 16.0.14334.20906 |
| Microsoft Office LTSC 2024 Product | >= 16.0.0, < 16.0.17932.20976 | 16.0.17932.20976 |
| Microsoft Office LTSC for Mac 2021 Product | >= 16.0.1, < 16.113.26091433 | 16.113.26091433 |
| Microsoft Office LTSC for Mac 2024 Product | >= 16.0.0, < 16.113.26091433 | 16.113.26091433 |