Network Connection Initiated To DevTunnels Domain

Detects network connections to Devtunnels domains initiated by a process on a system. Attackers can abuse that feature to establish a reverse shell or persistence on a machine.

Sigma rule (View on GitHub)

 1title: Network Connection Initiated To DevTunnels Domain
 2id: 9501f8e6-8e3d-48fc-a8a6-1089dd5d7ef4
 3related:
 4    - id: 4b657234-038e-4ad5-997c-4be42340bce4 # Net Connection VsCode
 5      type: similar
 6    - id: b3e6418f-7c7a-4fad-993a-93b65027a9f1 # DNS VsCode
 7      type: similar
 8    - id: 1cb0c6ce-3d00-44fc-ab9c-6d6d577bf20b # DNS DevTunnels
 9      type: similar
10status: test
11description: |
12        Detects network connections to Devtunnels domains initiated by a process on a system. Attackers can abuse that feature to establish a reverse shell or persistence on a machine.
13references:
14    - https://blueteamops.medium.com/detecting-dev-tunnels-16f0994dc3e2
15    - https://learn.microsoft.com/en-us/azure/developer/dev-tunnels/security
16    - https://cydefops.com/devtunnels-unleashed
17author: Kamran Saifullah
18date: 2023-11-20
19tags:
20    - attack.exfiltration
21    - attack.t1567.001
22logsource:
23    category: network_connection
24    product: windows
25detection:
26    selection:
27        Initiated: 'true'
28        DestinationHostname|endswith: '.devtunnels.ms'
29    condition: selection
30falsepositives:
31    - Legitimate use of Devtunnels will also trigger this.
32level: medium

References

Related rules

to-top