In order to have the best visibility on the status of user credentials in a network - have a look at UserLock. UserLock helps prevent outside attacks from compromised credentials, stops unauthorized network access, protects users from their own careless behavior, mitigates the actions of malicious insiders and will also ensure that any access to a company network (and resources inside) is attributed to the authorized individual employee. 

UserLock continuously monitors all network logon events, across all session types (including Wi-Fi, VPN and IIS), automatically applying custom policies that permit or deny authenticated users' access. (limiting concurrent logins, workstation/device restrictions, IP address restrictions, time restrictions etc). You can then track, report and immediately respond to any suspicious logon behaviour. 

With UserLock's layered security and real-time monitoring you can extend the way you easily verify a users' identity to offer the best protection against compromised credentials.