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Macon Computer Repair
There are hundreds of thousands of malicious programs out there and they are designed for different objectives. Most of them fall under the following categories:
To Take Control of a Computer
A common type of virus delivery system is the “trojan”. Trojans are sometimes installed unknowingly by the computer user from a file sent through instant messages or email attachments. Others are installed by the web browser running across “poisoned” web sites or ad servers. Once the computer has been infected, it becomes what the computer industry calls a “zombie”. The trojan joins a private chat channel and waits for orders. The bad guy gathers thousands of infected machines into a group called a “botnet” and uses them for attacks on web servers. Each of the infected computers sends a tiny bit of information to a web server, and because there may be thousands of computers doing this at once, it overloads the server, preventing access to it by other users. This is called a Distributed Denial of Service (DDoS) attack. The hacker may attack a rival web site, a government web site, or threaten to do so as part of an extortion plan. “Send me $5,000 or your toy selling website will be offline over the Christmas holidays”. The hacker can also use zombies to send spam while he remains anonymous and the blame goes to the infected computers. Botnets may also be used to host stolen software, illegal pornography, or other files the hacker doesn't want traced back to him.
To Steal Money
Some infections masquerade as spyware or virus removal programs. Once installed, the fake program pretends to scan your computer and “finds” viruses. It then says to remove them, you must pay for the “full version”. This is, of course, a lie. If you give them your credit card information, they’ve achieved their goal and start milking your credit or bank account.
To Steal Sensitive Information
Some viruses monitor traffic going in or out of a computer for information such as passwords or credit card numbers and send it back to the virus creator. These viruses may use keyloggers. Keyloggers are programs that keep a record of everything that is typed into the computer, such as emails, passwords, home banking data, instant messenger chats, etc. This method may allow an attacker to gather an incredible amount of data about a person which can be used for identity theft purposes. However, keyloggers are rare and don’t always work right, so they are one of the least used types of attack.
To Prove a Point, To Prove it Can Be Done, To Prove Ones Skill or For Revenge
A perfect example of this type of virus was the famous MS.Blaster virus (aka Lovesan) which infected hundreds of thousands of computers back in August 2003. This virus caused the system to restart after 60 seconds and had two hidden messages written in its code: One was “I just want to say LOVE YOU SAN!!” which is why the virus is sometimes called Lovesan, and the other message was “billy gates why do you make this possible? Stop making money and fix your software!!” It is believed that purpose of this virus was to prove how easy it is to exploit a Windows operating system.
To Cripple a Computer or Network
Few viruses intentionally disable computers because that stops their ability to spread to other computers. The worst computer crippling viruses were back in the days of the first personal computers, and the virus would overwrite the Master Boot Record of the computer, preventing the computer from starting up at all. Network crippling viruses are all too common. Most viruses that are designed to launch a Denial of Service attack will cause a significant load on a computer network, often bringing it down completely.