CVE-2021-1638: Microsoft Windows 10

High severity, CVSS 7.7. EPSS: 1.2% chance of exploitation in the next 30 days.

Microsoft is aware of the "Impersonation in the Passkey Entry Protocol" vulnerability. For more information regarding the vulnerability, please see this statement from the Bluetooth SIG. To address the vulnerability, Microsoft has released a software update that will fail attempts to pair if the remote device exchanges a public key with the same X coordinate as the locally exchanged public key

Affected products

• Microsoft Windows 10: version 20h2 only; version 1803 only; version 1809 only; version 1909 only; version 2004 only
• Microsoft Windows Server 2016: version 20h2 only; version 1909 only; version 2004 only
• Microsoft Windows Server 2019: affected versions not specified

Published 2021-01-12. Last modified 2026-06-17.