medium5.5
CVE-2026-21258
Improper input validation in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
Impact
Improper input validation in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Microsoft | 365 Apps | All versions |
| Microsoft | Excel | Version 2016 |
| Microsoft | Office | Version 2019 |
| Microsoft | Office Long Term Servicing Channel | Versions 2021, 2024 |
| Microsoft | Office Online Server | before 16.0.10417.20097 |