Steal or Forge Kerberos Tickets: Kerberoasting
- ID
- T1558.003
- Tactics
- TA0006 Credential Access
- Sub-technique of
- T1558 Steal or Forge Kerberos Tickets
- Platforms
- Windows
- Data sources
- Active Directory Credential Request, Process Access, Logon Session Creation, Logon Session Metadata
- Source
- attack.mitre.org
- MITRE last modified
- 25 Oct 2025
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.[2][1]
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 service[3]).[4][5][6][7]
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).[2][1] 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.[1][2] [7]
This same behavior could be executed using service tickets captured from network traffic.[1]
Cracked hashes may enable Persistence, Privilege Escalation, and Lateral Movement via access to Valid Accounts.[6]
Detection
- DET0157 Detect Kerberoasting Attempts (T1558.003)
Data components: Active Directory Credential Request, Process Access, Logon Session Creation, Logon Session Metadata
Mitigations (3)
- M1026 Privileged Account Management
Limit service accounts to minimal required privileges, including membership in privileged groups such as Domain Administrators.[1]
- M1027 Password Policies
Ensure strong password length (ideally 25+ characters) and complexity for service accounts and that these passwords periodically expire.[1] Also consider using Group Managed Service Accounts or another third party product such as password vaulting.[1]
- M1041 Encrypt Sensitive Information
Enable AES Kerberos encryption (or another stronger encryption algorithm), rather than RC4, where possible.[1]