Like others have already stated, this is your customer's problem and you should force the customer to correct the problem by letting them know they will not use your server to relay until they fix their problem.
John T eServices For You "Seek, and ye shall find!" > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:Imail_Forum- > [EMAIL PROTECTED] On Behalf Of Matti Haack > Sent: Monday, March 27, 2006 12:59 AM > To: [email protected] > Subject: [IMail Forum] SMTP-Relay / Auth only FROM valid email Adresses > > Hello, > > I have some problem with the way IMAL (8.x) handles SMTP-Auth email. A > customer from us seems to have a compromised host, which sends Spam > evry two weeks or so trough their local gateway - which is relayed over our IMAIL > Server. > > Their Mail server requires no authentification for their local hosts > to send mail - and does not sort out any invalid Mail-Froms. > > So this compromised host sends mail to thier internal gatway, which > relays the mail with smtp-Auth to our imail - The dictionary > attack-style Spam fills our mail queue with spam and bounces to the > fake from adress... > > Is there a possibility to reject mails from a host which connects via smtp-auth, if > the mail-from is not exisiting on the Server? > > We host some hundred virtual domains on one IPed host... > > Greetings > Matti > > > - > Matti Haack - Hit Haack IT Service Gmbh > Poltlbauer Weg 4, D-94036 Passau > +49 851 50477-22 Fax: +49 851 50477-29 > http://www.haack-it.de > > > > Dieses Dokument ist ausschliesslich fuer den Adressaten bestimmt. > Jegliche Art von Reproduktion, Verbreitung, Vervielfaeltigung, Modifikation, > Verteilung und/oder Publikation dieser E-Mail-Nachricht ist untersagt, > soweit dies nicht ausdruecklich genehmigt wurde. Jegliche Haftung fur > Ansprueche, die aufgrund der Kommunikation per E-Mail begruendet > werden koennten, ist ausgeschlossen, soweit der Haftungsausschluss > gesetzlich zulaessig ist. > > -- Ausgehende E-Mail wurde auf Viren gescannt -- > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
