Microsoft has confirmed that users can log into their Windows accounts using old passwords that have been changed and revoked under certain conditions. This behavior is classified as a feature rather than a security vulnerability. The issue arises from the Remote Desktop Protocol (RDP), which allows remote access to Windows machines. An independent security researcher discovered that after changing his password, he could still access his machine using the old credentials, even from new devices. Microsoft's documentation was updated to explain that credentials are verified against a local cached copy before network authentication, allowing continued access with the old password. Microsoft stated that this design ensures at least one user account can always log in, regardless of system offline status, and confirmed there are no plans to change this behavior.