sigmamediumHunting

Kerberos Network Traffic RC4 Ticket Encryption

Detects kerberos TGS request using RC4 encryption which may be indicative of kerberoasting

MITRE ATT&CK

credential-access

Detection Query

selection:
  request_type: TGS
  cipher: rc4-hmac
computer_acct:
  service|startswith: $
condition: selection and not computer_acct

Author

sigma

Created

2020-02-12

Data Sources

zeekkerberos

Platforms

zeek

References

https://adsecurity.org/?p=3458

Tags

attack.credential-accessattack.t1558.003

Raw Content

title: Kerberos Network Traffic RC4 Ticket Encryption
id: 503fe26e-b5f2-4944-a126-eab405cc06e5
status: test
description: Detects kerberos TGS request using RC4 encryption which may be indicative of kerberoasting
references:
    - https://adsecurity.org/?p=3458
author: sigma
date: 2020-02-12
modified: 2021-11-27
tags:
    - attack.credential-access
    - attack.t1558.003
logsource:
    product: zeek
    service: kerberos
detection:
    selection:
        request_type: 'TGS'
        cipher: 'rc4-hmac'
    computer_acct:
        service|startswith: '$'
    condition: selection and not computer_acct
falsepositives:
    - Normal enterprise SPN requests activity
level: medium