remote assistance for virus-infected p.c.?

[lng]

I want to help to remove a virus from a friend's pc. If I do so using remote assistance, do I risk infecting my pc?

[Tinto Tech]

With one important exception, no you are not at risk when running remote assistance.

The exception is if you transfer any file from the infected machine to your machine for further work.

A little background on that: even though you have established a data connection between the two machines, the malware would need to exploit a vulnerability in both ends to be able to traverse the network connection. Although theoretically possible in a spear phishing attack, it's highly unlikely. For all realistic purposes, remote assistance or any other remote connection protocol will prevent propagation of the malware between the two connected machines. The data that is transferred between the two machines is proprietary to the protocol and hence is not recognised as files by the file system of the assisting machine and hence cannot be used as an attack vector unless other mechanisms are used too.

The risk comes when one deliberately copies data files between the two machines. Any such data files will then be stored locally on the assisting machine and could potentially be infected prior to their copying from the target machine.

[lng]

in that case, I'll be careful not to transfer any files. thanks very much.

(his virus seems to have hijacked his email client and is sending messages to random people in his address book)

[BATcher]

Quite often a virus-infested PC is very slow, so remote controlling it might be even more agonisingly tedious....

[lng]

Hmmmmmmmmm. I think I'll email him some basic instructions to see if we can fix the pc that way, before accepting a remote assistance invite.

Thank you.