Re: [squid-users] prevent squid being used as spam passthrough

On 27/12/10 09:23, J Webster wrote:
> Is it possible for a proxy running on port 80 or 8080 to be used as a
> pass through or zone origination for spam email?

Maybe. If it has been configured as an open proxy.
http://wiki.squid-cache.org/SquidFaq/SecurityPitfalls

> We have had some users sign up with email addresses such as spambot and
> other stuff recently. I suspect these are just bots signing up around
> the web but got me thinking whether a proxy could be used in a chain or
> tunneled somehow and whether that could be blocked?

The default squid.conf http_access controls are designed to prevent this
type of thing.

It requires Safe_ports to list only the ports <1024 which are nown to be
safe for proxy connections-to. As well as SSL_ports for CONNECT tunnels
to only connect to known HTTPS ports.

You can see the quid default settings at
http://wiki.squid-cache.org/SquidFaq/ConfiguringSquid#Squid_configuration

Amos

-- 
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   Current Stable Squid 2.7.STABLE9 or 3.1.10
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