Skype is apparently conducting an “internal investigation” into the loophole, though for now there’s no official comment on when it might be closed off. If they were not logged in at the time, or not paying sufficient attention, then they could have their Skype credentials usurped – along with any credit on that account – without them even realizing it had happened.
Although a signed-in user will be able to see when somebody else attempts the hack, they would need to react fast in order to actually prevent themselves from being locked out.
