Prevent Mac Virus & Trojan Infection

The recent outbreak of the Flashback trojan has brought a lot of attention to potential viruses and trojans hitting the Mac platform. Most of what you’ll read is overblown fear mongering hype, and practically all Mac malware has come through third party utilities and applications. What that means for the average user is that it’s very easy to completely prevent infections and attacks from occurring in the first place, especially when combined with some general security tips. Without further ado, here are eight simple ways to secure a Mac to help prevent viruses, trojans, and malware from effecting you:

1) Disable Java

Flashback and other malware has installed through Java security breaches. Apple has already released several updates to patch the Java security holes that allowed Flashback to spread (you should install those), but you can also go a step further and completely disable Java on the Mac. Frankly, the average person doesn’t need Java installed on their Mac let alone active in their web browser, disable it and you don’t have to worry about security holes in older versions of the software impacting your Mac.

1a) Disable Java in Safari

  • Open Safari and pull down the Safari menu, selecting “Preferences”
  • Click on the “Security” tab and uncheck the box next to “Enable Java”

Disable Java in Safari

Disabling Java in the Safari browser is reasonably effective, but why not go a step further and disable it in Mac OS X completely? Chances are high that you won’t miss it, let alone notice it’s disabled.

1b) Disable Java System-Wide in Mac OS X

  • Open the Applications folder and then open the Utilities folder
  • Launch the “Java Preferences” application
  • Uncheck the box next to “Enable applet plug-in and Web Start applications”
  • Uncheck all the boxes next to “Java SE #” in the list below

Disable Java in Mac OS X

2) Update Apps and OS X Software Regularly

Apple regularly issues Security Updates and many third party apps do as well, therefore regularly updating both your OS X System Software and OS X apps are one of the single best preventative measures you can take to keep a Mac secure. We’ve hammered home about this repeatedly as a general Mac OS X maintenance tip because it’s important and so easy to do:

  1. Open Software Update from the  Apple menu and install updates when available
  2. Open the App Store and download available updates

3) Disable or Remove Adobe Acrobat Reader

Adobe Acrobat Reader has had multiple security breaches recently, therefore you’ll be safer without it in your web browser. There’s little reason to have Reader installed on a Mac anyway, OS X includes Preview for viewing PDF’s. Uninstall Adobe Acrobat Reader by running the bundled uninstaller app, or locate the following file and remove it to uninstall the Acrobat browser plugin:
/Library/Internet Plug-ins/AdobePDFViewer.plugin

4) Install Anti-Virus Software for Mac OS X

Using anti-virus software on the Mac is likely overkill, but it’s worth mentioning again. We’ve talked about the free Sophos anti-virus here before, and though you probably won’t ever need it, it’s a free and effective way to fight viruses that may end up on the Mac. If you’re the cautious type and you’d rather be safe than sorry there isn’t much harm to using it as a preventative measure:

5) Disable Adobe Flash / Use a Flash Block Plugin

Flash has been used as an attack vector in the past, and Macs stopped shipping with Flash installed for a reason; basically it’s a crash-prone battery hog that has occasional security breaches. Many sites use Flash for video and games though, so instead of uninstalling Flash completely we’ll recommend using a Flash block plugin for your web browser. This causes all Flash to be disabled by default until you click to allow individual plugins and instances of the Flash plugin to run, preventing unauthorized Flash from running in a web browser completely. These plugins are free and available for every major browser:

Flash block plugin for Safari

6) Disable Automatic File Opening After Download

Safari defaults to automatically opening “safe” files after they’re downloaded. For added security, disable this feature and manage the opening of downloads yourself:

  • Open Safari preferences and click the General tab
  • Uncheck the box next to “Open ‘safe’ files after downloading”

Disable Open Safe Files after downloading

7) Double-Check Anti-Malware Definitions are Enabled

OS X automatically downloads and maintains a malware definition list which is actively used to combat potential threats and attacks. This is enabled by default, but you can double-check to make sure you’re getting the updates as they arrive by insuring the feature is turned on:

  • Open System Preferences and click on “Security & Privacy”
  • Under the General tab look for “Automatically update safe downloads list” and make sure it is checked

You can also check the update list manually if you’re concerned the latest version hasn’t been installed, but as long as you have the feature enabled and have regular internet access, it probably is.

8 ) Don’t Install Random Software You Didn’t Ask For

If you see a random pop-up window asking you to install random software you didn’t request, don’t install it! This may sound like common sense, but it’s actually how some Mac malware propagated in the past. Apple patched the hole that allowed for that to happen a while ago, but the overall message is still relevant: if you didn’t download or request an app to be installed and you’re suddenly confronted with an installation dialog, don’t install it.

That about covers it, but if you have any additional security tips and anti-virus/malware/trojan tips, let us know in the comments.


Related Posts with Thumbnails

Comments are closed.