Solved

Recieving external spam with external email not working

Posted on 2004-10-06
5
289 Views
Last Modified: 2010-04-11
I have a interesting problem. I am recieving what seems to be external spam, but due to a dns issue we currently  cannot recieve external mail. What virus or spyware couold do this and how would I locate it.
0
Comment
Question by:smnphoenix
5 Comments
 
LVL 5

Accepted Solution

by:
zerofield earned 500 total points
ID: 12237496
if you arent receiving external email, or arent supposed to, sniff port 25 of your mailserver.  it's supposed to be very limited activity now anyway according to you.

if an upstream DNS server has cached your IP, and you're still online, it could just be "real" spam from the outside world.  I'd sniff the port briefly to check.  you can also use the exchange system manager to view current email connections and where they're coming from.
0
 
LVL 1

Expert Comment

by:Yaroslav_Buzko
ID: 12238193
I'd also advise to carefully examine the headers of spam messages. What are the IPs of server it comes through? Please post a whole header here if the problem persists.

Chances are that some user at your LAN got some malware sending out spam and pretending to be 'external'.
0
 
LVL 34

Expert Comment

by:PsiCop
ID: 12238432
Also, realize that not all spammers pay attention to DNS. Some just sweep the 'Net looking for hosts that answer on Port 25 and then try to spam. So unless you've shut down your SMTP daemon, anyone who can connect to port 25 can send you E-Mail. DNS does not HAVE to be involved.
0
 
LVL 6

Expert Comment

by:knoxj81
ID: 12240250
Well to answer you question about what virus could do this, and what you can do about it. I would just run a scan @ www.trendmicro.com and see if anything comes up. If not, you know your barking up the wrong tree.
0
 
LVL 2

Expert Comment

by:Snodlander
ID: 12256457
You may have an open relay on your exchange.
From an outside source see if you can telnet into your router on port 25 - post your results here
0

Featured Post

Free camera licenses with purchase of My Cloud NAS

Milestone Arcus software is compatible with thousands of industry-leading cameras for added flexibility. Upon installation on your My Cloud NAS, you will receive two (2) camera licenses already enabled in the software. And for a limited time, get additional camera licenses FREE.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
SQL 2012 database restore problem 6 66
yahoo Hacks 9 93
Knowb4 Compliance Manager vs Tripwire 2 58
Palo Alto Networks: Truly No Hit Count? 2 0
These days, all we hear about hacktivists took down so and so websites and retrieved thousands of user’s data. One of the techniques to get unauthorized access to database is by performing SQL injection. This article is quite lengthy which gives bas…
There are many Password Managers (PM) out there to choose from. PM's can help with your password habits and routines, but they should not be a crutch you rely on too heavily. I also have an article for company/enterprise PM's.
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, just open a new email message. In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, Just open a new email message.  In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…

911 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

21 Experts available now in Live!

Get 1:1 Help Now