277. Adversaries Abuse a Free Request Logging Service as C2

Hello everyone!

Today we'll talk about another interesting example of a legitimate web service, which is misused by threat actors as a C2 channel. This time it's a free request logging service.

According to Proofpoint report, TA415 leveraged requestrepo[.]com in order to exfiltrate collected system information as well as the VS Code Remote Tunnel verification code. 

The threat actors used WhirlCoil - a Python loader, which was executed via via pythonw.exe. We can use both facts to build a hunting query:

event_type: "dnsreqwin"

AND

dns_rname: "requestrepo.com"

AND

proc_file_path: "pythonw.exe"

See you tomorrow!

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