Suspicious Network Connection Initiated To Cloudflared Tunnels Domains (via network_connection)

title: Suspicious Network Connection Initiated To Cloudflared Tunnels Domains (via network_connection)
id: 5da756e6-4c70-58e4-9a03-647166018975
status: stable
description: This rule detects network connections to Cloudflared tunnels domains initiated by a process on the system. 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/T1567/
    - https://defr0ggy.github.io/research/Abusing-Cloudflared-A-Proxy-Service-To-Host-Share-Applications/
    - https://www.guidepointsecurity.com/blog/tunnel-vision-cloudflared-abused-in-the-wild/
    - Internal Research
author: Huntrule Team
date: 2026-01-27
tags:
    - attack.exfiltration
    - attack.command-and-control
    - attack.t1567
    - attack.t1572
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        Initiated: 'true'
        DestinationHostname|endswith:
            - '.v2.argotunnel.com'
            - 'protocol-v2.argotunnel.com'
            - 'trycloudflare.com'
            - 'update.argotunnel.com'
    condition: selection
falsepositives:
    - Unknown
level: medium