title: Cloudflared Tunnels Related DNS Requests
id: a1d9eec5-33b2-4177-8d24-27fe754d0812
related:
    - id: 7cd1dcdc-6edf-4896-86dc-d1f19ad64903
      type: similar
status: test
description: |
    Detects DNS requests to Cloudflared tunnels domains.
    Attackers can abuse that feature to establish a reverse shell or persistence on a machine.
references:
    - https://www.guidepointsecurity.com/blog/tunnel-vision-cloudflared-abused-in-the-wild/
    - Internal Research
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-12-20
tags:
    - attack.command-and-control
    - attack.t1071.001
    - attack.t1572
logsource:
    category: dns_query
    product: windows
detection:
    selection:
        QueryName|endswith:
            - '.v2.argotunnel.com'
            - 'protocol-v2.argotunnel.com'
            - 'trycloudflare.com'
            - 'update.argotunnel.com'
    condition: selection
falsepositives:
    - Legitimate use of cloudflare tunnels will also trigger this.
level: medium

title: Potential AS-REP Roasting via Kerberos TGT Requests
id: 3e2f1b2c-4d5e-11ee-be56-0242ac120002
status: experimental
description: |
    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.
references:
    - https://medium.com/system-weakness/detecting-as-rep-roasting-attacks-b5b3965f9714
    - https://www.picussecurity.com/resource/blog/as-rep-roasting-attack-explained-mitre-attack-t1558.004
author: ANosir
date: 2025-05-22
modified: 2025-07-04
logsource:
    product: windows
    service: security
detection:
    selection:
        EventID: 4768
        TicketEncryptionType: '0x17'
        ServiceName: 'krbtgt'
        PreAuthType: 0
    condition: selection
falsepositives:
    - Legacy systems or applications that legitimately use RC4 encryption
    - Misconfigured accounts with pre-authentication disabled
level: medium