Network segmentation is common in the enterprise but becoming more common in smaller environments.  If I compromise a box in my local segment and that box has access to another segment, we can use port forwarding to leap frog across.

The typical example has us making an actual connection which ties up one of our terminal sessions with an open ssh connection.  Fine, we can spawn a bunch of terminal sessions but we can also background it.

Read more: SSH Port Forwarding

I've spent a number of years bouncing back and forth between *nix machines and Windows machines.  But after the 90's, Windows really took hold and I've spent more hours on Windows than anything else and yet when I get a shell on a Windows machine, I feel like I have less control.  Scratch that, I HAVE less control but I can get what I want from outside of the box through PowerShell.

Read more: PowerShell Download Script

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Read more: #5.1.0 Address rejected.

Get a shell, lose a shell, get a shell, lose a shell.  That's basically what was happening while attacking this one particular box.  I'd get a shell and moments later my shell would close on me.  I had just enough time to drop into a command line but, poof, then it was gone.

Read more: Meterpreter session 1 closed. Reason: Died

I managed to find a small hole in a web application that appeared as if it wold allow me to execute commands on the local machine.  I tried a simple reverse shell but no joy.  Taking it down to a very basic level, I tried to ping but I needed to capture my ping requests on the other end.  

Read more: Catch ICMP (Ping) Requests

You get a shell on a linux box, you attempt to upgrade the shell to meterpreter using the command "sessions -u", and then you receive the following error:

"Shells on the target platform, linux, cannot be upgraded to meterpreter at this time."

Read more: Shells on the target cannot be upgraded...