Malware is everywhere online. If you're on the Internet, you're vulnerable to all manner of cybercrime: computer viruses, worms, and Trojan Horses that steal or corrupt your data. If you're not protected by grade A antivirus software, these cyber-bandits can turn your computer against you.
This is no abstract threat. In fact, you could already be the victim of malicious online attacks. You could be reading this on an infected computer right now. There are many types of viruses that operate without alerting you to their presence until it's too late. This computer virus list will teach you about the different kinds and what to watch out for.
What are the best ways to protect your computer from a virus? Of course, you need to be cautious about clicking on attachments and visiting suspicious sites, but it's a wild frontier. The best weapon in the old west of cyber crime is to install an antivirus software or Internet security suite, putting a firewall between you and malicious software so your data stays safe. The software also detects and removes viruses should you be unlucky enough to get one.
Just having antivirus software isn't enough though: you have to stay on top of software updates and run regular antivirus scans. Why? An update can mean a new virus is spreading, and your anti-malware software has found the cure. Actually, accepting regular updates for all your apps and software is recommended, as you never know which update is plugging a major security hole.
What It Does: Every time you open Word, you could be spreading one of these nasty little numbers. They infect all the documents on your hard drive, inserting unwanted text into every one and often making them unreadable. And the virus can send itself to everyone in your address book via email, turning you against your friends. A relatively new form of virus, this does just what the name implies, infecting macros in word processing programs. If a macro virus infects Word or Excel, for example, it will replicate itself in every Word or Excel document you create, scrambling the text and info in each one.
How You Probably Caught It: Being incautious when opening email attachments or unfamiliar documents.
Tip: Keeping current on security updates is especially important because macro viruses are so new and tough to detect using out of date software.
Slow-Infecting Resident Virus
What It Does: This one's like a houseguest you didn't even know was sleeping at your place, waiting until he's turned your whole family against you before burning your house down. A resident virus hides in your computer’s memory and wipes out data that you don't even realize is gone until you go looking. If you had a fast infector, you’d probably know by now, because they corrupt as many files as possible as rapidly as possible. These slow infectors, on the other hand, stay hidden by infecting only certain files at certain times, slowly chipping away at everything you save until there's nothing left.
How You Probably Caught It: By downloading a file or application, whether as an attachment, an illegal download, or a download from a disreputable source distributing malware. Once it was in your memory, it loaded a replication module in your operating system. You can protect your memory with Norton Antivirus, at a discount, on us!
What It Does: A stealth virus doesn't usually destroy data, but it does take over many of your computer's functions, slowing the machine down dramatically and maybe even rendering it useless. True to its namesake, a stealth virus uses camouflage to hide in your computer's memory, altering its size and keeping copies of your uninfected data to fool you when you’re hunting for it.
How You Probably Caught It: Downloading an email attachment from an untrusted source or installing software that's loaded with malware. With modern hacking, malicious code can actually come from reputable sites. Fun fact: The first ever computer virus, known as Brain, was a stealth virus.
Tip: If you suspect you have one, start the system by way of a disk boot then conduct an antivirus scan.
What It Does: You know all that annoying spam? There's a strong chance that your computer is sending spam, just one of the millions of unprotected machines conscripted into a botnet or zombie army. Technically, botnets aren't viruses, but once this malware is in your system, your computer is part of a network carrying out nefarious activities like spamming, identity theft, industrial espionage, extortion, and who knows what else. There are no symptoms, so your computer could be spamming for days, months, or even years, and you'd have no idea that you've been part of a zombie army until your identity's been stolen or your bank account's been ransacked.
How You Probably Caught It: Most bots are home computers with high-speed internet connections not protected by an adequate firewall. A Trojan Horse slips in through an open port and then you're part of a botnet.
Tip: Run an anti-malware app for sure, but you can also investigate your software firewall logs for any unusual approvals or activity and reset your firewall rules to be sure.