CVE-2026-55028: Microsoft 365 Apps

Medium severity, CVSS 5.5. EPSS: 0.6% chance of exploitation in the next 30 days.

Out-of-bounds read in Microsoft Office allows an unauthorized attacker to disclose information 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 16.0.19725.20434 (fixed in 16.0.19725.20434); version 2016 only; version 2019 only

Published 2026-07-14. Last modified 2026-07-16.