CVE-2026-27928: Windows Hello Security Feature Bypass Vulnerability

Overview

Severity
High (CVSS 8.7)
CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C
Category
Security Feature Bypass
Exploit Status
Not Exploited
Exploitation Likelihood
Less Likely
Patch Tuesday
2026-Apr
Released
2026-04-14

Description

Improper input validation in Windows Hello allows an unauthorized attacker to bypass a security feature over a network.

FAQ

According to the CVSS metric, successful exploitation could lead to a scope change (S:C). What does this mean for this vulnerability? This vulnerability could lead to the attacker gaining the ability to interact with other tenant’s applications and content. According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability? Successful exploitation of this vulnerability requires an attacker to prepare the target environment to improve exploit reliability. What kind of security feature could be bypassed by successfully exploiting this vulnerability? An attacker who successfully exploited this vulnerability could bypass the MFA required for Windows Hello for Business PIN provisioning. Where can I find more information about Windows Hello for Business PIN provisioning? Please see Windows Hello for Business PIN provisioning for updated details.

Affected Products (9)

Windows

  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server 2022
  • Windows Server 2022 (Server Core installation)
  • Windows Server 2025 (Server Core installation)
  • Windows Server 2022, 23H2 Edition (Server Core installation)
  • Windows Server 2025
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)

Security Updates (5)

Acknowledgments

sec-42a020b982ef, sec-42a020b982ef

Revision History

  • 2026-04-14: Information published.