Detectionmediumexperimental

Potential AS-REP Roasting via Kerberos TGT Requests

Detects suspicious Kerberos TGT requests with pre-authentication disabled (Pre-Authentication Type = 0) and Ticket Encryption Type (0x17) i.e, RC4-HMAC. This may indicate an AS-REP Roasting attack, where attackers request AS-REP messages for accounts without pre-authentication and attempt to crack the encrypted ticket offline to recover user passwords.

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Launch
ANosirCreated Thu May 22Updated Fri Jul 043e2f1b2c-4d5e-11ee-be56-0242ac120002windows
Log Source
Windowssecurity
ProductWindows← raw: windows
Servicesecurity← raw: security
Detection Logic
Detection Logic1 selector
detection:
    selection:
        EventID: 4768
        TicketEncryptionType: '0x17'
        ServiceName: 'krbtgt'
        PreAuthType: 0
    condition: selection
False Positives

Legacy systems or applications that legitimately use RC4 encryption

Misconfigured accounts with pre-authentication disabled

Rule Metadata
Rule ID
3e2f1b2c-4d5e-11ee-be56-0242ac120002
Status
experimental
Level
medium
Type
Detection
Created
Thu May 22
Modified
Fri Jul 04
Author
Path
rules/windows/builtin/security/win_security_kerberos_asrep_roasting.yml
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