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T1558.003 Kerberoasting

Adversaries may abuse a valid Kerberos ticket-granting ticket (TGT) or sniff network traffic to obtain a ticket-granting service (TGS) ticket that may be vulnerable to Brute Force.24

Service principal names (SPNs) are used to uniquely identify each instance of a Windows service. To enable authentication, Kerberos requires that SPNs be associated with at least one service logon account (an account specifically tasked with running a service1).6537

Adversaries possessing a valid Kerberos ticket-granting ticket (TGT) may request one or more Kerberos ticket-granting service (TGS) service tickets for any SPN from a domain controller (DC).24 Portions of these tickets may be encrypted with the RC4 algorithm, meaning the Kerberos 5 TGS-REP etype 23 hash of the service account associated with the SPN is used as the private key and is thus vulnerable to offline Brute Force attacks that may expose plaintext credentials.42 7

This same behavior could be executed using service tickets captured from network traffic.4

Cracked hashes may enable Persistence, Privilege Escalation, and Lateral Movement via access to Valid Accounts.3

Item Value
ID T1558.003
Sub-techniques T1558.001, T1558.002, T1558.003, T1558.004, T1558.005
Tactics TA0006
Platforms Windows
Version 1.3
Created 11 February 2020
Last Modified 24 October 2025

Procedure Examples

ID Name Description
S1063 Brute Ratel C4 Brute Ratel C4 can decode Kerberos 5 tickets and convert it to hashcat format for subsequent cracking.13
S0363 Empire Empire uses PowerSploit’s Invoke-Kerberoast to request service tickets and return crackable ticket hashes.10
G0046 FIN7 FIN7 has used Kerberoasting PowerShell commands such as, Invoke-Kerberoast for credential access and to enable lateral movement.2019
S0357 Impacket Impacket modules like GetUserSPNs can be used to get Service Principal Names (SPNs) for user accounts. The output is formatted to be compatible with cracking tools like John the Ripper and Hashcat.9
G0119 Indrik Spider Indrik Spider has conducted Kerberoasting attacks using a module from GitHub.21
C0049 Leviathan Australian Intrusions Leviathan used Kerberoasting techniques during Leviathan Australian Intrusions.22
C0014 Operation Wocao During Operation Wocao, threat actors used PowerSploit’s Invoke-Kerberoast module to request encrypted service tickets and bruteforce the passwords of Windows service accounts offline.23
S0194 PowerSploit PowerSploit’s Invoke-Kerberoast module can request service tickets and return crackable ticket hashes.127
S1071 Rubeus Rubeus can use the KerberosRequestorSecurityToken.GetRequest method to request kerberoastable service tickets.8
S0692 SILENTTRINITY SILENTTRINITY contains a module to conduct Kerberoasting.11
C0024 SolarWinds Compromise During the SolarWinds Compromise, APT29 obtained Ticket Granting Service (TGS) tickets for Active Directory Service Principle Names to crack offline.24
G0102 Wizard Spider Wizard Spider has used Rubeus, MimiKatz Kerberos module, and the Invoke-Kerberoast cmdlet to steal AES hashes.1815141716

Mitigations

ID Mitigation Description
M1041 Encrypt Sensitive Information Enable AES Kerberos encryption (or another stronger encryption algorithm), rather than RC4, where possible.4
M1027 Password Policies Ensure strong password length (ideally 25+ characters) and complexity for service accounts and that these passwords periodically expire.4 Also consider using Group Managed Service Accounts or another third party product such as password vaulting.4
M1026 Privileged Account Management Limit service accounts to minimal required privileges, including membership in privileged groups such as Domain Administrators.4

References

  1. Bani, M. (2018, February 23). Detecting Kerberoasting activity using Azure Security Center. Retrieved March 23, 2018. ↩

  2. EmpireProject. (2016, October 31). Invoke-Kerberoast.ps1. Retrieved March 22, 2018. ↩↩↩

  3. Medin, T. (2014, November). Attacking Kerberos - Kicking the Guard Dog of Hades. Retrieved March 22, 2018. ↩↩

  4. Metcalf, S. (2015, December 31). Cracking Kerberos TGS Tickets Using Kerberoast – Exploiting Kerberos to Compromise the Active Directory Domain. Retrieved March 22, 2018. ↩↩↩↩↩↩↩↩

  5. Microsoft. (2010, April 13). Service Principal Names (SPNs) SetSPN Syntax (Setspn.exe). Retrieved March 22, 2018. ↩

  6. Microsoft. (n.d.). Service Principal Names. Retrieved March 22, 2018. ↩

  7. Schroeder, W. (2016, November 1). Kerberoasting Without Mimikatz. Retrieved September 23, 2024. ↩↩↩

  8. Harmj0y. (n.d.). Rubeus. Retrieved March 29, 2023. ↩

  9. SecureAuth. (n.d.). Retrieved January 15, 2019. ↩

  10. Schroeder, W., Warner, J., Nelson, M. (n.d.). Github PowerShellEmpire. Retrieved April 28, 2016. ↩

  11. Salvati, M. (2019, August 6). SILENTTRINITY Modules. Retrieved March 24, 2022. ↩

  12. Schroeder, W. & Hart M. (2016, October 31). Invoke-Kerberoast. Retrieved March 23, 2018. ↩

  13. Harbison, M. and Renals, P. (2022, July 5). When Pentest Tools Go Brutal: Red-Teaming Tool Being Abused by Malicious Actors. Retrieved February 1, 2023. ↩

  14. DHS/CISA. (2020, October 28). Ransomware Activity Targeting the Healthcare and Public Health Sector. Retrieved October 28, 2020. ↩

  15. Kimberly Goody, Jeremy Kennelly, Joshua Shilko, Steve Elovitz, Douglas Bienstock. (2020, October 28). Unhappy Hour Special: KEGTAP and SINGLEMALT With a Ransomware Chaser. Retrieved October 28, 2020. ↩

  16. Shilko, J., et al. (2021, October 7). FIN12: The Prolific Ransomware Intrusion Threat Actor That Has Aggressively Pursued Healthcare Targets. Retrieved June 15, 2023. ↩

  17. The DFIR Report. (2020, November 5). Ryuk Speed Run, 2 Hours to Ransom. Retrieved November 6, 2020. ↩

  18. The DFIR Report. (2020, October 8). Ryuk’s Return. Retrieved October 9, 2020. ↩

  19. Abdo, B., et al. (2022, April 4). FIN7 Power Hour: Adversary Archaeology and the Evolution of FIN7. Retrieved April 5, 2022. ↩

  20. Loui, E. and Reynolds, J. (2021, August 30). CARBON SPIDER Embraces Big Game Hunting, Part 1. Retrieved September 20, 2021. ↩

  21. Mandiant Intelligence. (2022, June 2). To HADES and Back: UNC2165 Shifts to LOCKBIT to Evade Sanctions. Retrieved July 29, 2024. ↩

  22. CISA et al. (2024, July 8). People’s Republic of China (PRC) Ministry of State Security APT40 Tradecraft in Action. Retrieved February 3, 2025. ↩

  23. Dantzig, M. v., Schamper, E. (2019, December 19). Operation Wocao: Shining a light on one of China’s hidden hacking groups. Retrieved October 8, 2020. ↩

  24. MSTIC, CDOC, 365 Defender Research Team. (2021, January 20). Deep dive into the Solorigate second-stage activation: From SUNBURST to TEARDROP and Raindrop . Retrieved January 22, 2021. ↩