Given that this title is called Blue and is a Windows box, I assume that it based on the EternalBlue exploit. Just to check, we can run the SMB scanner in Metasploit.
Looks to be Windows 7 so things are looking up. MS17_10_eternalblue is the name of the exploit we are going to use:
If successful, it will give us a shell as seen below.
From here we can ‘cd’ to the administrators and users Desktop and read the txt file for the flag.