Exposing the Underground: Adventures of an Open Proxy Server
There's no need to portscan huge blocks of IP addresses looking for open proxy servers. Lists of open proxy servers can be found in seconds with a simple Google search. These lists are frequently updated, and some even include bandwidth statistics about each server. However, it should be noted that most of these proxy servers are not supposed to be public. It is very common to for a novice administrator to set up a proxy or HTTP cache with access rights from anywhere. There are programs available on the Internet to automatically redirect your traffic through different proxies. Some of these programs even chain proxies together for additional protection.
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