If accessed, you can write a webshell if web server is present (unlikely on default Win Metasploitable 3).
nmap -sS -Pn -p- --min-rate 1000 192.168.56.102 metasploitable 3 windows walkthrough
You can use auxiliary/scanner/smb/smb_login with common wordlists. If accessed, you can write a webshell if