Open relays and open proxies

Thu Apr 24 20:56:24 UTC 2003



--On Thursday, April 24, 2003 8:45 PM +0000 Paul Vixie <vixie at vix.com> 
wrote:

>
>> > I use proxycheck to manually check hosts for open proxies
>> > (http://www.corpit.ru/mjt/proxycheck.html)... you could script this (or
>> > a similar tool) and run scans of your entire network.
>>
>> That's what I would suggest.  You could also reactively test your
>> customers  when they make a connection to your webserver or mailserver.
>
> that won't catch the case where a proxy is open and is being abused but
> the resulting traffic is directed outside of the local isp, which is going
> to be the common case since parasites don't like to endanger their hosts.

True, but most people who end up with an open proxy trojan will also be 
using the machine to read their ISP provided email, etc