CVE-2026-45456: Microsoft 365 Apps

High severity, CVSS 8.4. EPSS: 0.4% chance of exploitation in the next 30 days.

Access of resource using incompatible type ('type confusion') in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected products

• Microsoft 365 Apps: affected versions not specified
• Microsoft Microsoft 365: affected versions not specified
• Microsoft Office 2016: affected versions not specified
• Microsoft Office 2019: affected versions not specified
• Microsoft Office 2021: affected versions not specified
• Microsoft Office 2024: affected versions not specified
• Microsoft SharePoint Server: before 16.0.19725.20384 (fixed in 16.0.19725.20384); version 2016 only; version 2019 only

Published 2026-06-09. Last modified 2026-07-23.