346. Hunting for Suspicious User Accounts

Hello everyone!

Adversaries often use compromised credentials, but in some cases they can create new accounts. And in some cases they are quite unique, so we can use it for detection and hunting.

As always, we need some examples. Let's look into this report. The adversary created new administrator accounts with the following names: backupadmin, admin_gpo and lapsadmin1. For example:

cmd.exe /c net user backupadmin abcd1234

Suspicious user creation events may be great targets for hunting, so make sure you document it not only for attribution and clustering, but also for detection:

event_type: "usercreatewin"

AND

usr_tgt_name: ("backupadmin" OR "admin_gpo" OR "lapsadmin1")

See you tomorrow!

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