Originally Posted by badman89
My friend's email account recently got hacked and emails were sent out to all of his contacts with malicious links. Himself and many others have confirmed that the link is some sort of Trojan horse. The links look like this: http ://t.co/9UHqh8PL. DO NOT OPEN!
This hasn't affected my Macbook Air (Snow Leopard) in any way that I can notice. Just wondering if it might have been affected in some way that I'm unable to notice (something subtle). How do I rule this possibility out?
Is your friend running Windows? It's most likely a Windows trojan, which cannot affect your Mac in any way, since Windows apps, including malware, cannot run on Mac OS X. Just delete the email and you'll be fine.
Macs are not immune to malware, but no true viruses exist in the wild that can run on Mac OS X, and there never have been any since it was released over 10 years ago. The only malware in the wild that can affect Mac OS X is a handful of trojans, which can be easily avoided by practicing safe computing (see below). Also, Mac OS X Snow Leopard and Lion have anti-malware protection
built in, further reducing the need for 3rd party antivirus apps.
Mac Virus/Malware FAQ
- Make sure your built-in Mac firewall is enabled in System Preferences > Security > Firewall
- Uncheck "Open "safe" files after downloading" in Safari > Preferences > General
- Change your DNS servers to OpenDNS servers by reading this.
- Be careful to only install software from trusted, reputable sites. Never install pirated software. If you're not sure about an app, ask in this forum before installing.
- Never let someone else have access to install anything on your Mac.
- Don't open files that you receive from unknown or untrusted sources.
- For added security, make sure all network, email, financial and other important passwords are long and complex, including upper and lower case letters, numbers and special characters.
- Always keep your Mac and application software updated. Use Software Update for your Mac software. For other software, it's safer to get updates from the developer's site or from the menu item "Check for updates", rather than installing from any notification window that pops up while you're surfing the web.
That's all you need to do to keep your Mac completely free of any Mac OS X malware that has ever been released into the wild. You don't need any 3rd party software to keep your Mac secure.
If you still want to run antivirus for some reason, ClamXav
(which is free) is one of the best choices, since it isn't a resource hog, detects both Mac and Windows malware and doesn't run with elevated privileges.