A New Security Problem I Am Dealing With. Suggestions?

[DVDR_Dog]

So a few days ago this new system shows up on a network scan. I have no idea who this might be. The network lists it as:
"Dead DESKTOP-01KNERN 192.168.0.99 G-PRO COMPUTER 00:23:24:50:F2:00".
The scan shows it as dead because I have blocked all packet traffic for mac 00:23:24:50:F2:00 in my gateway's rules.
I am able to enter the Public and Default accounts on this system before I did the mac filtering.
The only other info I am able to gather is it must be set-up for a static IP, and G-PRO COMPUTER ethernet chips are almost universally used by Lenovo PCs.

So it kind of bugs me to find this system plopped on my network. It almost has to be a wireless connection, yet I have no idea what it's intentions are.
Can anyone here give me some tips on how to mess with this system? It's mac has been filtered out for now, I just feel it's kind of ballsy what this system's operator has done. First time for me.

 

[Diguelo]

Hmm, without seeing it, this is a tough one. BUT ... I have dealt with this kind of issue on machines that used to be for use by Military and official services.

One thing always prevalent in these machines was insanly complex data path. Logic firmware controlled port access in and out and usually they had to be a defined monitor ir display array to see what went on in the machine. A standard screen wouldnt work as the Video bus went through encryption algorithms before going to the display units. Generally a packet of chips around the networking IC will be hardware coded and hardwired to use only certain code to access and enter.

Classically they were around the main network area of the board and attached hardwire to the RJ45 cosket on the back. Painin the ass to undo without schematics, but it was and is possible to remove the hardwired blocks IF you can get an original schamatic for the board. Most security board have the secure part on a daughter board and hidden it the display adapter out of sight. Coding MIGHT break into it, but it is highly unlikely. The hardwiring would just bin the new data and go on as if it never happened.

IF you can get the motherboard model number serial and trace it through the manucturer they may provide help..