Netconn from suspicious directories


Suspicious directories are an interesting topic and I am always on the lookout for them as a TTP.  The premise may be that directories like temp and downloads are already under review so some other directory should be used. That is fine for a while but once known it is easy to detect. The problem is noticing the unusual directory and adding it to your detection. I have no idea where I got most of these so if you have a post similar to this I will be happy to reference it.

Number one is the recycle bin, nothing should run from here, be referenced from here and certainly not netconn. I also do a signature for $recycle.bin in the command line just to catch anything non-netconn related.

These are locations to look for processes doing netconn.  Additional filtering is possible looking for activity from the root of these locations if you have a noisy one or it is a legit higher level path like C:\.

A search query for only the root would look something like this:

index=edr process_path=c:\\users\\public\\* process_path!=c:\\users\\public\\*\\*


$recycle.bin

c:\  ( netconn from the root only )
c:\users\public
c:\perflogs
c:\intel\logs
c:\users\default
c:\users\networkservice
c:\windows\fonts
c:\windows\debug
c:\windows\media
c:\windows\help
c:\windows\addins

c:\windows\security
c:\windows\repair
c:\windows\system32\config\systemprofile

HarddiskVolumeShadowCopy
c:\programdata\  (root only)

References:

https://twitter.com/SBousseaden/status/1133030955407630336
https://twitter.com/GossiTheDog/status/864957122114715653
http://blog.talosintelligence.com/2018/01/korea-in-crosshairs.html#more
https://twitter.com/cyb3rops/status/1098557657894531072






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