They say Sandvine’s PacketLogic filtering technology operated by Turk Telecom was, until recently, configured to silently redirect users toward downloads infected with spyware — a technique known as a man-in-the-middle (MITM) attack.
In this configuration, the Sandvine filter inspected traffic that passed through it, looking for attempts to download popular apps like VLC media player, Avast Antivirus and unofficial distributions of Skype.
If such a request came from one of 259 targeted IP addresses identified by Citizen Lab, the request would be redirected to a malicious copy — without the user knowing. If installed, the user would have been silently infected with spyware.
But there is a catch: the connections had to be unencrypted for the filter to see them taking place. For this reason, many websites now serve content, including file downloads, over encrypted connections, to thwart MITM attacks.
Source: They thought they were downloading Skype. Instead they got spyware – Technology & Science – CBC News
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