325. Can We Use Discovery Techniques for Hunting?

Hello everyone!

A very typical behaviour marker for many malware families - executing system discovery commands. And, of course, we can use it for threat hunting!

Let's look at TamperedChef campaign. The adversary performs registry query to look for the victim's machine ID:

reg.exe QUERY "HKLM\Software\Microsoft\Cryptography" /v MachineGuid

If we use it for hunting, we'll have to filter lots and lots of false positives, but still it may be a good hypothesis - just focus on parent processes.

In our example - it's quite suspicious as it's node.exe, so we can use it to build a query:

event_type: "processcreatewin"

AND

proc_p_file_path: "node.exe"

AND

proc_file_path: "reg.exe"

AND

cmdline: "machineguid"

See you tomorrow!

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