[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [suse-security] Email Spoofing
Hi *,
Tom Fox schrieb:
I¹d take a look at this URL:
1. Enforce reverse DNS lookups on the connecting IP address.
And Block almost any road warrior using dialup.
2. RBL subscriptions, for what those are worth.
Oh, Block the Rest ;-)
Another option (not necessarily recommended) is to force the "from" domain
to match the reverse lookup completed on the connecting IP address. This
will break many email attempts from legitimate sources because the SMTP
servers don't necessarily belong to the sending domain (MX gateway services,
for instances).
Right.
-----Original Message-----
From: Eric Kahklen [mailto:eric@xxxxxxxxxxx]
Sent: Wednesday, July 21, 2004 11:08 AM
To: suse-security@xxxxxxxx
Subject: [suse-security] Email Spoofing
We are using Suse 9.0 Professional. I am getting email that is claiming
to be from my domain and the Posfix logs confirm it is from an outside
IP.
Oh, why don`t you just block incomming SMTP Traffic
if the from: claims to be inside.
This is easy to configure.
Use ssl encrypted and accounted SMTP for allowed users.
(Road-Warriors)
You just need two IP, or two Ports and two instances
of postfix.
And you are RFC conform.
Greetings
Dirk
TRIA IT-consulting GmbH
Joseph-Wild-Straße 20
81829 München
Germany
Tel: +49 (89) 92907-0
Fax: +49 (89) 92907-100
http://www.tria.de
--------------------------------------------------------
working hard | for your success
--------------------------------------------------------
Registergericht München
HRB 113466
USt.-IdNr. DE 180017238
Steuer-Nr. 802/40600
Geschäftsführer:
Hubertus Wagenhäuser
--------------------------------------------------------
Nachricht von:
dirk.schreiner@xxxxxxx
Nachricht an:
tom@xxxxxxxxxx, suse-security@xxxxxxxx
# Dateianhänge: 0
Die Mitteilung dieser E-Mail ist vertraulich und nur für den oben genannten Empfänger bestimmt. Wenn Sie nicht der vorgesehene Empfänger dieser E-Mail oder mit der Aushändigung an ihn betraut sind, weisen wir darauf hin, daß jede Form der Kenntnisnahme, Veröffentlichung, Vervielfältigung sowie Weitergabe des Inhalts untersagt ist. Wir bitten Sie uns in diesem Fall umgehend zu unterrichten.
Vielen Dank
The information contained in this E-Mail is privileged and confidental intended only for the use of the individual or entity named above. If the reader of this message is not the intended recipient or competent to deliver it to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this E-Mail is strictly prohibited. If you have received this E-Mail in error, please notify us immediately.
Thank you
--
Check the headers for your unsubscription address
For additional commands, e-mail: suse-security-help@xxxxxxxx
Security-related bug reports go to security@xxxxxxx, not here