Profiling Scheduled Tasks


Watching for suspicious scheduled tasks is always a good thing but there are a lot of them so some creative categorization will be needed. This method is just to view tasks as they execute, not as they are being created.

Scheduled tasks should be the child process of svchost.exe so I started by breaking it into several different searches based on our normal suspicious scripting processes.

Powershell.exe
Cscript.exe
Wscript.exe
Mshta.exe
Cmd.exe

I'll use stats and pc counts again to self tune out those that are common to a given number of pcs. I run this back a couple of days so that the auto tuning kicks in.

Wscript Tasks



Add tuning as necessary to get rid of normal tasks and you "should" be able to get it down to a short list.
Repeat with the other target children and add any others that you like.

When I got to cmd.exe things started to get messy, there were way too many hits to filter so I limited it down to those with a path including "users" or "temp" and the search quieted down nicely.

This isn't perfect in that we are not looking at regular executables being started as tasks since there are way too many. We'll have to rely on our C2 sigs for those. This does provide a good breakdown on some suspicious process starts though.

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