190. Does Renaming Legitimate Binaries Really Mask Them?

Hello everyone!

Today I want to look at another stealer - NordDragonScan. Once again, the adversary uses a malicious LNK file to download an HTA - a very common behavior.

But it's not the thing that caught my attention, it's the following:

"The malicious HTA file copies the legitimate PowerShell.exe binary to the path “C:\Users\Public\Documents\install.exe” to mask itself"

So, here we have a renamed PowerShell.exe binary, and also quite suspicious staging folder - looks like the adversary made things even noisier!

We already talked about renamed system binaries, and here's another example:

event_type: "processcreatewin"

AND

proc_file_originalfilename: "powershell.exe"

AND NOT

proc_file_name: "powershell.exe"

And also another suspicious staging folder:

event_type: "processcreatewin"

AND

proc_file_path: "Public\\Documents"

See you tomorrow!

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