HP Norton Personal Firewall 2003 manual Likelihood of being attacked

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Understanding Internet risks

The likelihood of being attacked

A zombie program is a dormant program secretly installed on a computer. It can later be run remotely to aid in a collective attack on another computer. Zombie programs don’t normally damage the computer on which they reside, but are used to attack other computers. A zombie program can arrive as an email attachment.

Norton AntiVirus protects you from receiving and executing viruses, Trojan horses, worms, and zombies. Norton AntiVirus scans email as you receive it and also checks files when you open them, providing two levels of protection.

Norton Personal Firewall ensures that Trojan horses do not communicate over the Internet. This means that you are protected from hackers who use Trojan horses.

The likelihood of being attacked

The Internet presents many risks. What are the odds that your computer will be attacked? The chance of an attacker singling out your computer from all of those on the Internet is slim. However, the use of port-scanning and other computer discovery tools by hackers means that your computer may be scanned relatively frequently for vulnerabilities. The more vulnerabilities that are found, the more inviting your computer is to hackers.

The tools that hackers use to find targets can scan large groups of computers on the Internet. The hacker simply enters a range of IP addresses to be scanned. The program checks each IP address in the range to see if a computer is there. If it finds a computer, it performs a series of tests to identify vulnerabilities, such as having Microsoft networking enabled over the Internet. The hacker returns to find a list of computers and their vulnerabilities.

Norton Personal Firewall protects you from these scans by making your computer invisible. Your computer won’t respond to queries that these scanners send. This means that your computer exhibits no vulnerabilities to the hacker, making it a poor target for attack.