CVE-2026-21514: Microsoft Word Security Feature Bypass Vulnerability

Overview

Severity
High (CVSS 7.8)
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Category
Security Feature Bypass
Exploit Status
Actively Exploited
Exploitation Likelihood
Detected
Publicly Disclosed
Yes
Patch Tuesday
2026-Feb
Released
2026-02-10
EPSS Score
4.25% (percentile: 88.8%)
CISA KEV
Listed — due 2026-03-03

Description

Reliance on untrusted inputs in a security decision in Microsoft Office Word allows an unauthorized attacker to bypass a security feature locally.

FAQ

According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do? An attacker must send a user a malicious Office file and convince them to open it. What kind of security feature could be bypassed by successfully exploiting this vulnerability? This update addresses a vulnerability that bypasses OLE mitigations in Microsoft 365 and Microsoft Office which protect users from vulnerable COM/OLE controls. Is the Preview Pane an attack vector for this vulnerability? No, the Preview Pane is not an attack vector.

Affected Products (8)

Microsoft Office

  • Microsoft 365 Apps for Enterprise for 32-bit Systems
  • Microsoft 365 Apps for Enterprise for 64-bit Systems
  • Microsoft Office LTSC for Mac 2021
  • Microsoft Office LTSC 2021 for 64-bit editions
  • Microsoft Office LTSC 2021 for 32-bit editions
  • Microsoft Office LTSC 2024 for 32-bit editions
  • Microsoft Office LTSC 2024 for 64-bit editions
  • Microsoft Office LTSC for Mac 2024

Security Updates (1)

Acknowledgments

Anonymous, Microsoft Threat Intelligence Center (MSTIC), Microsoft Security Response Center (MSRC), and Office Product Group Security Team, Google Threat Intelligence Group, Anonymous

Revision History

  • 2026-02-10: Information published.