Using a VPN service like ipredator in Sweden to share files with some level of security using BitTorrent or similar methods has become very popular as more tough laws pass to address Internet piracy. However, for those using IPv6 in combination with a PPTP-based VPN, a flaw may have undermined the entire idea of the VPN in the first place.

A security flaw was revealed at the Telecomix Cipher conference that would allow a third party to find the true IP address of a user sharing through a VPN. To make matters worse for some users, there are suggestions that anti-piracy investigators in Sweden at least are aware and may have been exploiting the flaw to identify "anonymous" sharers.

IPv6 is set to replace the IPv4 protocol, but most users using IPv6 arguably have no idea they are, as it is promoted by newer operating systems like Windows 7.

The operators of ipredator are aware of the issue and have said they will contact all users about it. Other privacy-based VPN services may want to do the same thing. Simply turning off IPv6 in Local Area Connection properties on Windows should serve as a workaround for the problem.

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