07 Sneakiest Computer Viruses

As more computer users become wise to viruses, the criminals behind them are often a few steps ahead. Some malware infects your computer without you ever realizing it and then can truly mess up your life. Others arrive as a result of user mistakes, then do their dirty work undetected. We've got the scoop on 15 of the most devious and crafty viruses currently out there, including information on how they can harm you and tips on how to protect yourself against them. Click on below to find out more....

Sneakiest Computer Viruses

'Sinowal' Trojan Horse

The next time you upload pictures from your birthday bash or post comments to your favorite social networking site, you may be doing more than putting your reputation on the line and online. You may also be exposing your bank account data to a pretty sneaky Trojan horse.

A Trojan horse called Sinowal, a variant of the Mebroot trojan we reported on back in January, has to date gathered details of more than 500,000 online bank accounts, and may be one of the most advanced and dangerous security risks on the Web, according to Internet security firms that track these sorts of things. The scary thing is that a user doesn't need to click on a pop-up window or do anything else traditionally seen as risky -- the Trojan downloads to the user's computer in the background automatically the minute a user clicks on an infected link.

While initially found mostly on random, unsecure Web sites, the Trojan is now finding its way to popular social networking sites like Facebook and MySpace, where it can sometimes be found in those random postings you get on your wall.

This so-called "drive-by" infection is just one of many cropping up all across the Internet, with as many as 1 in 10 sites showing some kind of malicious software risk, according to a Google estimate. How to protect yourself? Unfortunately, not much can be done other than being wary of clicking on anything that seems to random or unfamiliar on popular sites. You can also download a free copy of GMER, which purportedly gets rid of this menace.

Sneakiest Computer Viruses

Giant Security Holes

As is the case with any real-world fortress, most computer operating systems have security holes and flaws somewhere – it's just a matter of whether the computer company or computer hackers discover them first. Such is the case with a recent security hole discovered on computers running Windows XP, Windows 2000, and Windows Server 2003. The hole essentially leaves computers totally open to hackers, with no involvement from computer users at all! Luckily, Microsoft last week discovered this flaw and took the rare step of immediately releasing a security patch before any evildoers could wreak havoc. If you haven't updated your Windows machine with the latest security patches, then do so immediately. You should have already been updated if your computer is set to Automatic Updates in the Control Panel (click on Start, then Control Panel, then Automatic Updates). You can also download the patch yourself by going to the Microsoft Download Center.

Sneakiest Computer Viruses

The Storm Worm

This virus is one of the nastiest and most prolific out there. It's a backdoor Trojan - malicious software disguised as a harmless program - that is spread to PCs via fake news and holiday greeting card e-mails. Once infected, your computer becomes part of a botnet, a network of computers running and spreading the malware at an alarmingly fast rate -- so essentially your computer not only slows down, but also serves as a perpetrator of the crime. How to protect yourself? Don't open any files in e-mails from people you don't know, turn on your e-mail program's spam prevention tool, and make sure your virus protection software is up-to-date.

Sneakiest Computer Viruses

Mal/Hupig-D

That Obama sex tape e-mail we told you about contains this devious virus. Mal/Hupig-D runs in the background of Windows and steals your passwords, credit card information, and the like. Virus scanners look for it now, but rely on your common sense first and don't click on that e-mail. If you'rew worried that your computer might be infected with it, don't enter your passwords or credit card information until you get it looked at by a computer professional.

Sneakiest Computer Viruses
Facebook Virus

We know you may love those funny videos your friends send to you on Facebook, but you may have to forgo clicking on any links from friends in the near future. That's because a Trojan horse that purports to be a legitimate e-mail from a Facebook friend actually contains W32.Koobface worm, which looks for a cookie on your computer that enables it to take over your Facebook account and send itself to all your friends! Here's what to watch out for: E-mails that have flattering subject lines about who a hot crush someone has on you, or how great you look in some video.

The e-mail itself will have a link to a YouTube like link that leads you to a fake YouTube page. On that page, you're asked to download a video player upgrade. Whatever you do, don't download and install that upgrade, or your machine will be infected. But before you even get to that point, you might just double-check with your friends who like to send videos to make sure what they've sent is legit. It may take the fun out of video sharing, but better safe than sorry!

Sneakiest Computer Viruses

OSX/Hovdy-A

Sorry, Mac users, but you're in danger too. This Trojan affects computers using Mac OS X 10.4 or 10.5, and lets the bad guys use your Apple Remote Desktop agent for a host of disturbing activities. The virus can be used to monitor your keystrokes, transmit passwords, turn on file sharing, take screenshots, and, creepiest of all, take pictures with the built-in iSight camera -- all unbeknownst to you! It's spread through downloads that you have to agree to, so if you stay sharp, avoid sketchy utilities, and keep your anti-virus protection current, you'll be fine.

Source: switched.com