5.5
Medium
CVE-2026-21258 Improper input validation in Microsoft Office Excel allows an unauthorized attacker to disclose information locally
Description
Improper input validation in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Office Online Server 16.0 | 16.0.0.0 → < 16.0.10417.20097 | 16.0.10417.20097 |
| 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 → < 16.106.26020821 | 16.106.26020821 |
| 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 → < 16.106.26020821 | 16.106.26020821 |
| Microsoft Excel 2016 16.0 | 16.0.0.0 → < 16.0.5539.1002 | 16.0.5539.1002 |
References
- Microsoft Excel Information Disclosure Vulnerability msrc.microsoft.com
Timeline
- Published
- Last modified
Other CVEs of Office Online Server
The 200 CVEs of Office Online Server →
CVE-2026-108446
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network
8.8
High
CVE-2026-100210
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code over a network
8.8
High
CVE-2026-100212
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network
8.8
High
CVE-2026-97772
Double free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network
8.8
High