050. Detecting Dirty Wolf's Tunneling Tool

Hello everyone! Let's talk a bit about tunneling tools. They are extremely common nowadays. I think, everybody heard about Ngrok, right? But what about less common tools?


Activity cluster we track under the name Dirty Wolf is constantly using the following tunneling tool - Localtonet. The cluster is involved in ransomware attacks and leverages leaked LockBit 3.0 builder to generate payloads.

So, let's look at Localtonet detection opportunities. As always, we can look at executable files' metadata to cover renaming as well as command line parameters (usually it's just "authtoken"):

event_type: processcreate

AND

proc_file_originalfilename:"localtonet.dll"

AND

cmdline:"authtoken"

If the adversary uses Localtonet infrastructure (and it's a very common case), we can build detection logic based on DNS queries (make sure you exclude security solutions):

event_type: "dnsreq"

AND

dns_rname: ("localto.net" OR "localtonet.com")

AND NOT

proc_file_path: ("kaspersky" OR "windows defender")

See you tomorrow!

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