enum4linux
Tool for enumerating Windows and Samba information from remote systems.
TLDR
Try to enumerate using all methods
$ enum4linux -a [remote_host]
Enumerate using given login credentials
$ enum4linux -u [user_name] -p [password] [remote_host]
List usernames from a given host
$ enum4linux -U [remote_host]
List shares
$ enum4linux -S [remote_host]
Get OS information
$ enum4linux -o [remote_host]