I discovered my server has been used to relay a fair amount of spam 
over the last few days, and in doing the investigation behind it, it 
turns out ASSP is the hole that they got through. Version 2.0.0 
15.06, in particular, however I tested with 15.11 and it does the 
exact same thing.

First off: I have my listenPort2 and smtpAuthServer set, so that my 
users can connect and send mail through my server. I also have 
EnforceAuth set - however, upon investigation, anyone can connect to 
my mail server, and without doing SMTP Auth, in a simple plain SMTP 
session, pretend to be anyth...@anyofmydomains, and send mail to any 
valid user on my server. Thankfully, if the user attempts to send 
mail to a third party on a domain not hosted by me, it rejects it 
with "530 SMTP authentication is required", so it's not wide open. 
However, it is quite clearly ignoring EnforceAuth.

Which brings me to my second problem. With my v1 ASSP, it was set up thusly:

1. Anyone could connect on port 25 and send mail from any user to any 
user on my server, with no auth required. This is an obvious public 
SMTP server.

2. Users could connect on port 25 or 125 with SMTP Auth, and could 
send mail from themselves (MAIL FROM had to be a known user on the 
server) to any email address.

#1 is working, as you would expect. However, #2 is not working. The 
way it is currently functioning is: any user who has a valid account 
on my server, can log in via SMTP AUTH, and send mail from ANY email 
address, to ANY email address, and my server will happily relay it. 
This is where the spam problem comes in - One of my users had their 
PC compromised, and their SMTP password stolen by a trojan. This was 
then used to log into my server from zombie spam bots and send 
massive amounts of spam all over the world. This spam had "MAIL FROM" 
various spammy places, not my local domains. Normally, if it was 
working as it should, this would not have been permitted - the only 
way the SMTP AUTH session should be able to send mail is if the mail 
is from a valid user on the server.

noProcessingIPs contains a small list of IPs, primarily containing a 
web server that sends mail through my mail server.
noProcessingList contains one email address.
noProcessingDomains:=

acceptAllMail contains the same list of IPs as is used for noProcessingIPs.
DoLocalSenderDomain:=1
DoLocalSenderAddress:=1
nolocalDomains:=
ispip:=
contentOnlyRe:=
ispHostnames:=

LocalAddresses_Flat:=file:files/users.txt
localDomains:=file:files/domains.txt
(these are both updated regularly by my mail server)

noMsgId contains the same list of IPs as is used for noProcessingIPs.

DoNoValidLocalSender:=1
ForceNoValidLocalSender:=1
DoNoSpoofing:=1
DoLocalSender:=1

Am I missing something? Do I have something configured incorrectly? 
Or is there a problem here in ASSP itself? I've been over the 
configuration many times now, and I don't see what I could have set 
up incorrectly.



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