Microsoft: Security keys may prompt for PIN after recent updates

BleepingComputer

November 26, 2025 at 2:43 PM

Overview

Microsoft has alerted users that FIDO2 security keys may require a PIN for sign-in following recent Windows updates since September 2025. This change could affect user experience and security practices, particularly for those relying on these security keys for authentication.

Key Takeaways

Affected Systems: FIDO2 security keys, Windows operating system (updates since September 2025)
Action Required: Users should check for the latest Windows updates and follow any guidance provided by Microsoft regarding the use of FIDO2 security keys.
Timeline: Disclosed on [date]

Original Article Summary

Microsoft warned users on Tuesday that FIDO2 security keys may prompt them to enter a PIN when signing in after installing Windows updates released since the September 2025 preview update. [...]

Impact

FIDO2 security keys, Windows operating system (updates since September 2025)

Exploitation Status

The exploitation status is currently unknown. Monitor vendor advisories and security bulletins for updates.

Timeline

Disclosed on [date]

Remediation

Users should check for the latest Windows updates and follow any guidance provided by Microsoft regarding the use of FIDO2 security keys.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to Windows, Microsoft, Update.

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