1
vote
1answer
240 views

“From:” e-mail header spoofing - how to verify such mail?

I'm facing a problem of verifying a "From:" message field in e-mail messages, in terms of e-mail spoofing. I am currently using SPF and DKIM to verify the origin and integrity of messages, but as far ...
0
votes
1answer
198 views

Tracking anonymous e-mail threat

A user spoofed/sent an email from http://emkei.cz/ with a very serious threat. Is it possible to trace this back or are we SOL? There wasn't much in the email headers other than that it came from ...
0
votes
3answers
785 views

Exchange and SPF Records

I've created an SPF record on 123-Reg, which is working great. But my question is how Exchange servers know that an SPF record exists when they receive mail from a domain. How does Exchange know it ...
3
votes
3answers
234 views

How to Limit the Damage of Domain Spoofing

My e-mail account, for my privately run business which I'll call "VeryCoolCompany", is starting to receive bounce-backs for users who don't exist, like these: alan12ab1@verycoolcompany.com ...
0
votes
1answer
199 views

Blocking External Mail Sent w/ Spoofed Email Address

We recently got an email from an outside server that had a spoofed "From:" header that was the email address of one of our users. Is there a way to have sendmail reject emails coming in from an ...
1
vote
1answer
156 views

Preventing Email Spoofing

I use Google Apps with my domain. Recently, we have begun to receive spam that gets past Google's spam filters. They are from our own email addresses. I am wondering how to prevent this kind of ...
2
votes
2answers
2k views

Reject obviously spoofed messages in Exchange 2007 SP2

I have an Exchange 2007 SP2 server which happily accepts SMTP messages whose sender is SomeRandomString@mydomain.com and the recipient is SomeRealUser@mydomain.com; this leads to all sort of spoofing ...