North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Misguided SPAM Filtering techniques
On Sun, Oct 21, 2007, Nathan Ward wrote: > Blocking 25/TCP is acceptable, blocking 587/TCP is not - it is > designed for mail submission to an MSA, so serves little use for > spam, save when a spammer has detected an open mail relay listening > on 587/TCP, or someone has (mis)configured port 587 to allow > submission to locally hosted domains from remote hosts without > authentication. I'd be /very/ surprised if the networks in question > received sufficient complaints from (clueless) mail admins, who were > being spammed via one of these techniques. Or peoples' machines are now being infected by malware which checks for login credentials or uses the existing mail client via various inter-process communication techniques; re-using said login credentials to talk to authenticated SMTP servers. Gotta get a clue; its not enough to just authenticate who sent the email anymore.. Adrian
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