If your on the internet your getting attacked by malicious software constantly. Most firewall software won't log or notify you of it because it's pointless information. They just work, the only time they mention anything is when something goes wrong.
As far as individual attackers, they are constantly scanning for vunerable computers. I can setup a bash script to scan my local ISP's IP address range and find you maybe 20 or 30 Windows computers that are online and operating without firewalls.
Out of those I'd probably find 5-10 that have ports open high in the address range. This means that they are running some sort of service, and since people don't run services on Windows machines, generally, it means that probably half of those are backdoors.
A person with a simple scanner can do thousands of scans in just a few minutes. This stuff goes on constantly.
This isn't what if's, this is what goes on now.
What your doing now is exactly like leaving your car parked in a massive multilevel public parking lot. Constantly there are dozens of people wondering around and checking out potential targets. Putting your car behind a NAT/router or high quality firewall is like parking your car in a garage with a alarm system every night.
The chances of them targetting you specificly are fairly small. One in a hundred. Like a pickpocket in a crowd, chances are they won't bother with you. But it still happens.
Like my Grandma just a few months ago was a target of wire fraud. She was recently widowed and of course they post that information in the paper. People scan thru the obituaries because most females of her age don't deal with finances and are greiving and lonely and thus are easy targets for con artists.
They somehow obtained her credit card information, nobody figured out how, and charged her 400 some dollars. She found out about it and called the bank and credit card people and canceled the card and they refunded her. A few weeks later the con guys called her and told her that they received the 400 dollar down payment that her husband paid for for a trip to somewere in the caribbean. If she didn't want to go (after all her husband just died) they were more then willing to completely refund her for the amount if she would only give them details about her checking account so they could wire her the money back.
Some people are real pig-fvkers. It's not a question of paranoia. There are a few things you can do to protect yourself and your a fool not to take advantage of it.
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