Can viruses spread in an a wireless network that sharing only internet connection?

[ILoveIL]

Hi I have an old computer running Win XP and recently I want to connect it to the internet. To do so I will need to hook it up to my home net. I don't care if this computer will be infected (due to the security breaches no longer being closed) however I don't want it to compromise the other computers on the net. My friend told me that I have nothing to be worry about because as long the net is sharing the internet connection only (the computers are undiscoverable to each other) a virus can't spread from one computer to the others. Please can you tell me if he is right?

 

[Rabmac]

Firstly, I need to point out that I am not an expert but from my understanding, malware can spread to other machines on the network and can even infect the router.

If you are concerned this may happen you may want to disconnect your other devices before you hook this up.

 

[ILoveIL]

Even if the computers are undetectable

 

[Rabmac]

Why are the other computers undetectable?

From my understanding, a hacker would be able to see every device connected to a network if they wanted to.

 

[ILoveIL]

Cause you define that windows won't share data between PCs

 

[Rabmac]

That is by no means fail safe, although it does add an extra layer of protection.

Here is a possible scenario.

Computer A get infected by malware but computer B and computer C are not visible at present. The malware infects the router next, now it can see all the computers on the network and has an open port into computer B and computer C.

Now I am not saying this will happen, merely saying that it is possible and if you want to keep the other computers 100% safe, it may be best to disconnect them from the network while you do what you need to do with the XP machine.