Most Mac users, including myself, feel pretty secure from the nastier bits of the web. It is a false sense of security however, and only a matter of time before more and more hackers turn their beady little eyes towards our shining tower on the hill. Last week SecureMac discovered a trojan horse that can affect our systems and is spreading through social networking sites like Facebook.
The trojan masquerades as a video often attached to the phrase: “Is this you in this video? Click here to find out.” The trojan then runs as a Java applet, downloading files to your computer. These files include an automatically launching installer that will modify system files to bypass the need for passwords. This process opens the gates by allowing outside access to your system. This sneaky little bugger also runs invisibly and in the background at startup and will periodically check in with command servers to report info on your system. There have been reports of infected computers spreading the trojan through email and other social media sites.
The best defense against attacks like this is to simply not click on suspicious links, and stay away from the seedier side of the web. But if you simply can’t avoid the shadows you can also run antivirus software on your computer. Though be prepared to have them slow your system down significantly, especially if they’re always scanning your files. I run ClamXav (http://www.clamxav.com/) myself. It’s free, lightweight, and uninstalling it doesn’t kill your system like Norton can. It also seems to have the least performance-affecting processes out of all the antivirus programs out there.
Another good tip is to have a strong password set up on your computer. A blank password is not secure, nor is having your password show up as the password hint. As a service technician at Small Dog, I see all sorts of passwords and the majority of them are not very good. You’d also be surprised at how many passwords I’ve been able to guess just by seeing the hint and having access to just a little bit of owner information like address or telephone number. A strong password will be made up of numbers, letters and symbols with at least one letter capitalized and the entire password will be at no less than 12 characters. You should also make use of the built in security features of Mac OS X, like the firewall. If you really want to get paranoid (though not so far as wearing a tinfoil hat and taping over your iSight camera) you should periodically change all your passwords.
Finally, another way to monitor your system is through an application like Little Snitch, which will monitor all outgoing communication by your computer. You can permit and deny communications process by process. It can be a bit much for the novice to set up and maintain, but for those with the know-how it’s a good tool.
To help defeat the trojan, SecureMac has put together a tool that will remove the trojan from your system if it has been infected. The tool can be directly downloaded from this link: http://macscan.securemac.com/files/BTRT.dmg