Very Computer

Recently I found that my machine, running AIX 4.2.1 sendmail UCB 8.7, was
used by someone as a relay to send a lot of junk mails. How to prevent this
from happening again?

D J Guan

You should update to at least 8.9.x, where relaying problem can be solved...

A

Quote:> Recently I found that my machine, running AIX 4.2.1 sendmail UCB 8.7, was
> used by someone as a relay to send a lot of junk mails. How to prevent
this
> from happening again?

> D J Guan

Check sendmail.org.  I believe that they have a fix for 8.7.  Best answer is
upgrade to 8.9 (actually I think it is up to 8.11 now).  4.3.3 includes 8.9.
5.1 has an even more recent version.

The easiest way to do this is to upgrade to AIX 4.3.3 if this is a
practical proposition (note that AIX 4.2.1 is out of support). It's
still an open relay by default, but there is a document published by IBM
which tells you how to fix it. Go to
http://techsupport.services.ibm.com/rs6k/techbrowse/, select view by
product/subsystem, then mail, and you will see a document "Configuring
Anti-Spam in AIX 4.3.3".

Sendmail 8.9.3 (as shipped with AIX 4.3.3) will build OK on AIX 4.2.1,
or you can get a binary of 8.9.2 from
http://www-frec.bull.com/docs/download.htm, but there is no facility for
building sendmail.cf with the M4 macros, so you would have to do it the
hard way. The 4.3.2 version of the above document might help a bit. I
cheated and built the .cf on AIX 4.3.3 and copied it over. You can
probably upgrade M4 from source too, or get it from Bull, but I have not
tried this. See also the sendmail FAQ section 5.2:
http://www.sendmail.org/faq/section5.html#5.2. The instruction in 5.2.1
is necessary if you want to run sendmail compiled from source under src
control. I assume that IBM modified their version of sendmail to avoid
this, as it isn't needed with their binary. I don't know about Bull's.

Regards, Ian