It’s called a “Denial of Service” attack and it comes from a virus, affectionately named as you can see in the snippet above, “Smurf”.
Three packets won’t, in themselves, cause a problem. The targeted computer will look, judge them worthless and then toss ’em over it’s shoulder.
But the Smurf virus is intended to infect hundreds, thousands, easily tens of thousands of computers on the Internet. By having each of them send a few “taps” of packets at the same time, the effect is devastating.
Thirty thousand packets arriving in the space of a few seconds is more than most internet services can tolerate. Multiply that number by a hundred if Smurf reaches a million infestations and it’ll bring down even the biggest servers on the Internet. None of them are safe.
My sick computer is an old Linux box running CentOS 6. Infections (viruses) there are rare and, compared to Windows, relatively easy to cure. That’s now in progress.
If you have a firewall, it probably creates a log of suspicious activity both coming in and also going out. There is probably an option in your firewall’s configuration to have it send you that log by email. I have mine set to do that once a month. It’s mostly a boring read but, in this case, it turned up a problem.
Who knows what evil lurks in the hearts of men?
Check your firewall log and you, as well as The Shadow, might find out.