Suspicious Cloudflared Tunnels Related DNS Requests (via dns_query)

title: Suspicious Cloudflared Tunnels Related DNS Requests (via dns_query)
id: d765c7fc-4b4c-5513-95b3-99f36cfc1e3d
status: stable
description: This rule detects DNS requests to Cloudflared tunnels domains. Attackers can misuse that feature to establish a reverse shell or persistence on a machine.
references:
    - https://attack.mitre.org/techniques/T1572/
    - https://attack.mitre.org/techniques/T1071/001/
    - https://www.guidepointsecurity.com/blog/tunnel-vision-cloudflared-abused-in-the-wild/
    - Internal Research
author: Huntrule Team
date: 2026-01-29
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:
    - Unknown
level: medium