SB20260414142 - Multiple vulnerabilities in Microsoft Windows Hello

Description

This security bulletin contains information about 2 vulnerabilities.

1) Input validation error (CVE-ID: CVE-2026-27906)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to gain access to sensitive information on the system.

The vulnerability exists due to insufficient validation of user-supplied input in Windows Hello. A local administrator can bypass protection mechanisms and gain access to sensitive information on the target system.

2) Input validation error (CVE-ID: CVE-2026-27928)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to insufficient validation of user-supplied input in Windows Hello. A remote attacker can bypass the MFA required for Windows Hello for Business PIN provisioning.

Remediation

Install update from vendor's website.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27906
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27928