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Another issue is that open proxy servers are often operated by hackers, Internet "con-artists", and people with similar intentions. All they really want to do is collect personal information from you, which they will easily accomplish if you use their proxy server carelessly. If you've used free proxy servers in the past, you might have wondered why those proxy servers were often and suddenly shut down. This is very often due to the fact that the operator accounts were created by individuals using stolen credit card information. When they are discovered, these proxies are quickly closed by the providers.
Hackers commit many illegal acts, including credit card fraud. They simply wait for you to use your financial information (including CC info, bank, passwords, etc.) while you are connected to their proxy server, and that's that. Make no mistake, the server operators/admins can, and very likely will, read all your traffic and use it in any way they want to.
The bottom line is: If you use a free proxy server, you are running the risk of being an identity theft victim, and your computer could even be used to commit crimes without your knowledge.
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