enum
Enum is a console-based Win32 information enumeration utility. Using null sessions, enum can retrieve userlists, machine lists, sharelists, namelists, group and member lists, password and LSA policy information. enum is also capable of a rudimentary brute force dictionary attack on individual accounts. inux-ng -P 172.16.5.5 -oA ilfreight
Installation
Download it from: https://packetstormsecurity.com/search/?q=win32+enum&s=files.
Basic commands
# Enumerates shares
enum.exe -s $ip
# Enumerates users
enum.exe -u $ip
# Displays the password policy in case you need to mount a network authentification attack
enum.exe -p $ip