Hi I need some help and advice if possible about email, net security and hacking.

My best friend has zone alarm firewall and norton antivirus ( his definitions are up to date)
He hardly downloads things from the internet and has also checked for spyware with ad-aware and spybot. Virus scan shows no virus at all, neither does trojan hunter.

About 12 months ago I begun receiving email from someone who was sending personal information about my friend to me. Stuff like his mobile phone numbers, copies of his business card, home address and so on.

A month or two back more emails began arriving, this time they contained details about my friend's upcoming weekend break, complete with Hotel name and date of stay. Other emails came that were non specific but were slightly harassing. The IP address matched a woman we both knew, her ISP.
The HELO also said the EXACT name of her computer, also said the name of her partners half of the computer, EXACT name next to HELO.

My question is, how is this possible? She is trying to say that she must have been hacked and that the information that was sent to us was by a hacker, but how would a hacker know my email address because he does not have this on his computer at all. Would a hacker be able to mimic her EXACT helo, IP address and monitor info and then use that info to email me? Why didnt the hacker hack the credit card my friend used to book his holiday instead of emailing me?, it doesnt make sense at all.

His IP address is dynamic so surely the hacker wouldnt be able to continually monitor the computer anyway and what about the firewall?

Can anyone please shed light on it?
Why would a hacker just want to harass me, how would a hacker know me and how would hacker be able to mimic her exact IP addy , helo and ISP?
And the other thing is, if a hacker DID managed to hack him, could he send an email from the hacked computer that would replicate the HELO and IP address or would that take on the Hackers helo and IP?

Thanx, Karen

As I understand it, if a trojan was dropped on her computer and her computer was taken over by a hacker, yes, all that could be done. Hackers/virus spreaders often use another person's computer to broadcast viruses to those in the person's addy list, thus hiding the hacker's address and getting his victim into trouble when traced.

As to the why's of your personal problem with this person, only you can answer that. Whether she was actually hacked or not...?

Basically, all the technical details are possible. It's also possible, and more likely, someone is lying. Let's put it this way: What's the point of sending you hand-made email if the "hacker" doesn't know you? In fact, consider how much the "hacker" would have to go out of their way to make this whole thing happen. They would have to link you and the others involved together, research one, forge the email of another, all to send you email about what they learned. Now ask the first question again. Sounds like a bad movie, either way.

It is one of many common Email worms!
Randomly sending out personal documents from her hard drive to randomly selected Email addresses in her address book!
Then, when you, or anyone who recieves this random mailing opens it (because you think it is from someone you know) the worm then does the same thing on your computer, and so on, and so on...

There are now many varients of this worm and it can be hilarious or tragic, depending on what is sent and to whom!

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