This masquerade ended when apps seeded with BadNews got a prompt from one of three command and control servers, then it started pushing out and installing a more malicious programme called AlphaSMS. This steals credit by sending text messages to premium rate numbers.

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If someone tries to contact the user, their action is recorded by Microsoft's servers, which then send a notification, reactivating Skype so it can handle the activity.

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Then, when you want to chat over Skype, the call is routed over a regular mobile network which then connects to iSkoot's servers.

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