I don’t trust Skype. I suspect its doing things to my Linux computer that I did not authorize. Far too often I’ve seen CPU usage spike on Skype for no apparent reason. Today that happened again. I clicked on the close button and Skype dutifully disappeared from my desktop, but the process itself kept running in the background!
I’ve read rumors of things Skype may be doing behind our backs, but didn’t treat them seriously until now. I’m starting to believe any peer-to-peer (or instant messaging) apps deserve close scrutiny, regardless of the reputations of the companies that create them. If a hacker hacked Skype’s main servers, for instance, she could potentially have access to millions of PCs running Skype clients. Don’t you think that’s an inviting target?
If I was in charge of a network with sensitive data, I’d ban Skype in a heartbeat.
Read these papers offering a technical security critique of Skype: Vanilla Skype 1, and Vanilla Skype 2. Also, the obligatory Wikipedia entry: Skype Protocol.