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Why do I see requests for foreign sites appearing in my log files?
An access_log entry showing this situation could look like this:
63.251.56.142 - - [25/Jul/2002:12:48:04 -0700] "GET http://www.yahoo.com/ HTTP/1.0" 200 1456
For this log line, the 200 code (second to last field in this example) indicates that the request was successful – but see below for an explanation of what “success” means in this situation.This is usually the result of malicious clients trying to exploit open proxy servers to access a website without revealing their true location. They could be doing this to manipulate pay-per-click ad systems, to add comment or link-spam to someone else's site, or just to do something nasty without being detected.
It is important to prevent your server from being used as an open proxy to abuse other sites.