149. Adversaries Abuse Free Web Hosting Infrastructure

Hello everyone!

Let's talk a bit about threat actors' infrastructure. As you know, adversaries need to store malicious files somewhere in order to distribute them. Of course, they can use their own infrastructure, but in many cases they opt to freely available variants.

For example, APT41 (we track this cluster as Wanted Werewolf). The threat actors abused various free web hosting tools for distributing their malware.

What does it mean? We can use it for hunting:

event_type: "dnsreq"

AND

dns_rname: ("workers.dev" OR "trycloudflare.com" OR "infinityfreeapp.com")

What's more, the threat actors Google Calendar for C2!

See you tomorrow!

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