There has been quite a stir in the tech world lately in the wake of an announcement by anti virus company Dr. Web that the OSX/Flashback trojan downloader has recruited over 600,000 unsuspecting Apple computers to the emerging Mac botnet. This has since been confirmed by Kaspersky Labs.
Since Apple computers are extremely popular among creative professionals, I thought it might be helpful to impart some practical advice to any fellow readers and Mac users who might be concerned. So let’s start off by getting the elephant out of the room…
I thought Macs didn’t get computer viruses?
This is perhaps the biggest fallacy regarding Apple computers – it’s simply not true. Unfortunately, Apple have been quite comfortable in the past about peddling this myth and making light of the users’ responsibility when it comes to security issues. For the sake of clarity, I’m going to use the term “virus” and “malware” (malicious software) interchangeably. There have been many senseless arguments about the strict definition of the various subsets of malicious software but the point remains the same – it is hostile code and you need to know how to detect it and remove it.
How do I know if I’m infected or not? And how do I remove it if I am?
Fortunately, because malware for Macs is so rare it is still practical to use manual detection and removal methods, and there are many good write ups and user support forums to help you. Ars Technica has a really useful article that covers both questions and provides solutions for each. This particular piece of malware is estimated to affect between 1 and 2% of Macs at the time of writing – it is up to you to decide whether following these instructions is a good use of your time.
How do I prevent this from happening in the future?
I deal with computer security issues on an almost daily basis. Here are my top three tips for improving your chances when it comes to avoiding malware:
1. Keep your software up to date and properly configured
New software trumps old software when it comes to security, and this counts for both the operating system (OSX) and any additional software you might have installed. Make sure you restart your Mac regularly to install pending automatic updates.
Apple do not offer extended security support for their previous versions of OSX, so even if you feel like your Mac is only a few years old you might be more obsolete than you think. Any version before OSX 10.6 “Snow Leopard” is currently unsupported. If you need to buy an upgraded version of OSX then I recommend doing so, but check compatibility with your hardware first.
In regards to keeping additional software up to date, this is just as – if not more – important than keeping OSX up to date. A huge percentage of malicious software gains access to computers through vulnerabilities in software like Flash Player and Java. If you use these pieces of software, make sure you update them regularly and if you don’t use them uninstall them from your machine.
Additionally, consider enabling the built-in firewall for OSX and disabling the automatic opening of “safe” files downloaded with Safari.
2. Get your software from trusted sources
Use of pirated software and its associated tools is another significant malware risk. If you get software from file sharing services or similar sources, you are potentially handing over the keys to your computer and trusting the person who packaged the file and uploaded it not to do anything malicious.
Apple recognize this and are on the curve with the availability of the Mac App Store as a trusted repository to purchase, download and update your software. Future versions of OSX are set to be more restrictive in the installation of software from unknown sources.
3. Consider using anti virus software
Anti virus software is not a silver bullet. I don’t even rate it as the most important defense against malware. It is, however, a useful tool and should be considered as part of a ‘defense in depth’ approach. Anti virus software is much maligned for slowing down computers, but that really depends on the individual product and configuration. You should at least try it for yourself. Sophos currently offer a free anti virus product for Mac users.
I hope that’s at least given you a heads up about the situation regarding Macs and malware, and steps you can take to help yourself. Taking a bit of responsibility and being pro-active can keep your computer protected and healthy, and let us get back to using them creatively.