I noticed that Norton (Internet Security 2011) blocked two intrusion attempts by HTTP Nukesploit and Crime Pack activity 1 at the same time earlier tonight. The attacking computer was my own.
I've read through a few forums and I'm a little confused. A number of people seem to have had very similar experiences, but the responses vary from a diagnosis of a serious infection (followed by a horrendous series of scans and reports), to a reassurance that Norton has blocked a random attack - don't worry about it.
I've noticed that intrusion attempts are not uncommon, but the fact that these purport to be from my machine is rather unsettling.
Should I be worried?