Can we get infected w/malware by using Remote Assistance to fix an infected PC?

[Ken90630]

I have a few handfuls of friends/acquaintances that I help with computer problems on a regular basis. There are instances when I could use Remote Assistance rather than driving over to their house or office. I've never used it before now, but I'd like to start.

I'm wondering: If I connect to a PC that happens to be infected with, say, a worm or other piece of malware designed to spread itself to other connected drives or PCs on their network, can my PC get infected?

And if the answer is yes, how do the big companies (Dell, Symantec, etc.) keep their tech support people's computers from being infected all the time (since they do a lot of remote assistance)?

 

[RebateMonger]

No, not unless you allow the remote PC access to your disks. Even then, it's doubtful.

 

[Ken90630]

No, not unless you allow the remote PC access to your disks. Even then, it's doubtful.

Cool. Two new questions, however:

1. When using Remote Assistance, doesn't that constitute setting up a temporary 'network' of sorts? And if so, wouldn't a worm designed to identify all connected networks try to spread itself over those networks?

2. Re allowing the remote PC access to my disks, would that be disallowed by default or would I need to do something to restrict that access? And if so, what?

Don't mean to seem dense -- I've never used RA before and am on the steep side of the learning curve (short as it may be).