CVE-2026-40364CriticalCVSS 8.4

Microsoft Word Remote Code Execution Vulnerability

Published
May 22, 2026
Last Modified
—

🔗 CVE IDs covered (1)

📋 Description

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

🎯 Affected products12

  • Microsoft 365 Apps for Enterprise for 32-bit Systems
  • Microsoft 365 Apps for Enterprise for 64-bit Systems
  • Microsoft Office 2019 for 32-bit editions
  • Microsoft Office 2019 for 64-bit editions
  • Microsoft Office LTSC 2021 for 32-bit editions
  • Microsoft Office LTSC 2021 for 64-bit editions
  • Microsoft Office LTSC 2024 for 32-bit editions
  • Microsoft Office LTSC 2024 for 64-bit editions
  • Microsoft Office LTSC for Mac 2021
  • Microsoft Office LTSC for Mac 2024
  • Microsoft Word 2016 (32-bit edition)
  • Microsoft Word 2016 (64-bit edition)

✅ Remediation

KBClick to Run (Security Update) — fixed build https://aka.ms/OfficeSecurityReleases KBRelease Notes (Security Update) — fixed build 16.109.26051019 KB5002858 (Security Update) — fixed build 16.0.5552.1000

🔗 References (5)