073. Detecting RMMs from Ransomware Affiliate's Toolkit: FleetDeck

Hello everyone! Yes, ransomware. Again. Let's look at another RMM abused by adversaries - FleetDeck. I don't see it very often, but there're even public reports showing it's leveraged by by ransomware affiliates, for example, ALPHV.


By the way, this legitimate remote access tool has a very interesting slogan on its website - "Command and Control".

Let's start from DNS requests to fleetdeck[.]io:

event_type: "dnsreq"

AND

dns_rname: "fleetdeck.io"

The tool isn't very common, we can hunt for processes executed from default installation location:

event_type: "processcreatewin"

AND

proc_file_path: "FleetDeck Agent"

The installer also uses PowerShell (yes, again) to create a new firewall rule:

powershell.exe -Command "New-NetFirewallRule -DisplayName 'FleetDeck Agent Service' -Name 'FleetDeck Agent Service' -Direction Inbound -Program 'C:\Program Files (x86)\FleetDeck Agent\fleetdeck_agent_svc.exe' -Action Allow"

Of course, we can detect it:

event_type: "processcreatewin"

AND

proc_file_name: "powershell.exe"

AND

cmdline: "NetFirewallRule" AND "FleetDeck"

Finally, let's hunt for the agent itself:

event_type: "processcreatewin"

AND

proc_file_productname: "FleetDeck Agent Service"

As you can see, it's quite noisy, and you have lost of detection opportunities, so it's important just to look for similar activity.

See you tomorrow!

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