074. Detecting Ransomware Affiliate's Toolkit: Cloudflared

Hello everyone! Let's keep talking about modern ransomware affiliate's toolkit. Today we'll look at defense evasion and command and control capabilities.

I came across this CISA advisory on Medusa Ransomware, and spotted the following tool - Cloudflared. It's used to securely expose applications, services, or servers to the internet via Cloudflare Tunnel without exposing them directly. Of course, adversaries abuse this feature!

To create a tunnel, the threat actor should run the following command (or just run the installer, it creates a service and runs the command):

cloudflared.exe tunnel run --token [redacted]

Not very common command line arguments, right? Let's use it to build detection:

event_type: "processcreate" 

AND 

cmdline: ("tunnel" AND "run" AND "token")

Have you observed any other interesting tunneling tools ITW recently?

See you tomorrow!

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