high7.5
CVE-2026-21511
Deserialization of untrusted data in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.
Impact
Deserialization of untrusted data in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Microsoft | 365 Apps | All versions |
| Microsoft | Office | Version 2019 |
| Microsoft | Office Long Term Servicing Channel | Versions 2021, 2024 |
| Microsoft | Sharepoint Server | before 16.0.19127.20518 Versions 2016, 2019 |
| Microsoft | Word | Version 2016 |