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

On 29/12/10 06:28, J Webster wrote:
> That's pretty much what I have but is it not possible to use one of
> these ports as a pass through for spam or would the receiving email
> servers block it?

One would hope the mailservers are configured to block it (involves
special detection and reject on HTTP headers in the SMTP). Unfortunately
this is not always true.

The main protection is in stopping Squid from connecting to a possible
SMTP port in the first place.

And yes, if the SMTP is listening on an unusual port its possible the
proxy may allow connections to it anyway. This is only best-effort
security since HTTP and SMTP can each be extended slightly to pass as
native traffic of the other protocol.

Amos

-- 
Please be using
   Current Stable Squid 2.7.STABLE9 or 3.1.10
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