I’m getting lots of email messages at my yahoo address with “returned email: user unknown” and like phrases in the subject line. Most of these have nothing coherent, except sometimes a link to a porn site.
Are these just strange-looking spam messages or do I have more to be concerned about? I am already closing down my yahoo account because I can’t seem to get these kinds of messages to consistently go to the junk basket.
That’s spam.
I get a lot of those messages. What happens is that a spammer uses your email address as the “from” address in the spam that they dump on the Internet. When the recipient’s mail server can’t deliver the message, such as when the mailbox is no longer valid, it sends a notification back to the forged “from” address. Some spammers use random “from” addresses, or if they are mad at someone, they will send out millions of spam messages with the “from” address set to that of their enemy.
Technically, it’s spoofing, not spam. It’s more common with viruses than spammers (who don’t need to use a real address at all).
Most viruses these days set up their own mail server and send out e-mail to every e-mail address on the infected machine. (This can include e-mail addresses in web page, so it does not have to be anyone you ever actually sent e-mail to.) They also pick one address at random to be the sender.
Systems often automatically send off notifications to the “sender” if there’s a problem delivering e-mail. If you were the one chosen to be the “sender,” you’ll get the mail.
The messages can be ignored.
You can just delete these things, or note them as Junk. If that is just too much of a hassle, stop that acount with Yahoo and start another with a different name (hey, it’s free).
Thanks, but does that mean people are getting freaky porno emails that look like they were sent from my address?
Yes, and possibly virus infected mail as well, but there’s not much you can do to prevent the forgery of your e-mail address by either a spammer or a virus. However, many folks are aware of this and the practice of sending hate mail back to the From: address is (thankfully) becoming less and less popular, at least if you’re lucky.
Not to disagree with others who have contributed to this thread (“ignore and delete” is certainly a valid option), but if the bounce messages that you’re receiving happen to include the extended headers of the original piece of mail that prompted the bounce (which depends on how the bouncing mailserver is configured), you can file an Abuse complaint with the network of origin of the original e-mail. If the network is a responsible and responsive one, this will result in the owner of the system/account responsible for sending the mail that forged your address being contacted and hopefully secured.
If you want further details of how to go about doing this, there are some old threads of mine that discuss interpreting headers. I’ll see if I can dig one up.
Taking a little bit of time to be a good netizen with such bounces will likely result in one less compromised system/account being used to spew crap into the ether. It might seem inconsequential, but if enough folks did it more often, we might actually make a difference for a minute…at least untill the next virus comes along.
I can’t seem to find any old posts of mine that walk through header interpretation, but I just found this handy site that does a nice job:
http://combat.uxn.com/tracing.html
They even include a place for you to cut and paste the IP of origin from any abusive/suspicious mail you wish to report, and it spits out the appropriate Abuse department contact address at the responsible network.