7.8
High
CVE-2026-20957 Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally
Description
Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Office Online Server 16.0 | 16.0.0.0 → < 16.0.10417.20083 | 16.0.10417.20083 |
| Microsoft Office 2019 19.0 | 19.0.0 → latest | No fix stated |
| Microsoft 365 Apps for Enterprise 16.0 | 16.0.1 → latest | No fix stated |
| Microsoft Office LTSC for Mac 2021 16.0 | 16.0.1 → < 16.105.26011018 | 16.105.26011018 |
| Microsoft Office LTSC 2021 16.0 | 16.0.1 → latest | No fix stated |
| Microsoft Office LTSC 2024 16.0 | 16.0.0 → latest | No fix stated |
| Microsoft Office LTSC for Mac 2024 16.0 | 16.0.0 → < 16.105.26011018 | 16.105.26011018 |
| Microsoft Excel 2016 16.0 | 16.0.0.0 → < 16.0.5535.1000 | 16.0.5535.1000 |
References
- Microsoft Excel Remote Code Execution Vulnerability msrc.microsoft.com
Timeline
- Published
- Last modified
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