Viral Infections of the Digital Kind
Computers have become a big part of our everyday lives. We use them for work, play, shopping, learning; the list goes on and on. Yet along with all this convenience comes the risk of attack. There are people who, in spite of their intelligence and programming skills, apparently have nothing better to do than write programs that cause all kinds of trouble in computer systems. They do this by finding and exploiting system vulnerabilities- loopholes that allow unwanted actions to take place. This malicious software, or malware, as it is commonly known, can be merely annoying, doing things like displaying messages, playing sounds, or rearranging the icons on the desktop, or downright destructive, corrupting files, causing the computer to run slow or crash, or even formatting the hard drive, destroying everything on it. It can steal personal information such as passwords, account numbers, and social security numbers so an attacker can steal your identity or access your bank accounts.
The term "computer virus" is commonly used to describe any malicious software, but there are actually different types of malware. Among these are viruses, worms, trojan horses, and logic bombs. A virus is a small program that hides within a file or another program and runs when the file or program is opened. It then replicates itself, infecting other files, goes to work interfering with the normal operation of the computer, and looks for a way to spread to other computers. It may also search network connections for other computers, or send itself to entries in an e-mail contact list. Infected files are often unknowingly downloaded from websites, or spread through a home or company network. They are also often spread via floppy disks, CDs, flash drives, or any other removable media.
A worm is similar to a virus however a worm does not need to be attached to a file, but is a self-contained executable file. A worm can also execute itself without any action by the user, so a computer can be infected just by opening an e-mail message, downloading a file, or just visiting a malicious website. Some worms, rather than altering the data on a computer, work by spreading and clogging the system, taking up excessive hard drive space, RAM, or network bandwidth.
A trojan horse is a malicious program that is disguised as something legitimate like a screen saver or even anti-virus software. They don't usually self-replicate, but instead spread through deception. You should be very careful what programs you download and install. Offers of free software in pop-up ads or spam are often not what they claim to be.
A logic bomb is a type of malware that hides and waits for a particular event to occur before releasing its fury. It might be activated at a certain date and time, if a company's employee is terminated, or by a number of other possible triggers.
Malware can cause a wide variety of problems. Some signs that your computer may have been infected by a virus or other malware include:
The computer runs slower than normal.
The computer frequently crashes, restarts spontaneously, or won't boot up.
E-mail contacts receive messages from you that you didn't send (especially with attachments).
Programs don't run correctly, won't open, or disappear.
Hard drive space or RAM unexplainably runs low.
So how do you keep yourself safe from these attacks? The best defense against viruses and other types of malware is education (know how to recognize suspicious e-mails, websites, software offers, and the signs of an infection), keeping your operating system updated to repair known vulnerabilities, and the proper use of up-to-date antivirus software to detect and eliminate attacks. There are several good AV programs available such as Norton, McAfee, and AVG that do a good job of preventing infection by viruses and other malware. These should be updated frequently, as new viruses are being released every day, and they should be scheduled to perform a complete system scan at least weekly, if not daily.
Even though there are many threats lurking out there, we can remain safe if we use some common sense and keep our operating system and antivirus software up-to-date.