This year has been relatively silent with regard to malware in OS X, but today security and antivirus firm Intego reported that the criminals behind the Flashback Trojan have been hard at work releasing new variants to their malware package. The seventh variant of Flashback has been identified, which shows it is using new and unique techniques for infecting Macs.
Flashback is a Trojan horse attack that, according to Intego, now uses numerous methods for infecting Mac systems. First it will try to take advantage of Java security holes to install itself, but if you do not have Java installed (OS X 10.7 and later are shipped without a Java runtime), then it will try to use various social engineering methods to trick users, such as disguising itself as a legitimate Adobe Flash installer and displaying certificates that appear to be from Apple in order to coerce people to run the Trojan installers.
Once installed, the Trojan will inject code into Web browsers and other specified applications like Skype in attempts to harvest passwords and other information from those who use these programs. Luckily the affected programs generally crash, which is a good indicator that something is wrong with them and they will need to be reinstalled or otherwise addressed; however, there is chance that if infected the Trojan might have been successful at getting the information it was after.
While the level of Mac malware is exceptionally minimal in regard to the malware scene for the entire PC industry, it is out there, so be cautious about what you download and open on your system. If you are uncertain about whether your system is safe, then you can always install a malware scanner and keep it up to date with the latest malware definitions. You do not need to set the scanner to always scan your system, but instead can have it monitor your downloads folder, e-mail, and other locations that might be more apt to have malware should you run into it.
This latest news on Flashback adds to the few reports we've seen this year, and it is likely that more will follow. Last year saw the most malware to date being released for OS X, suggesting a potential increase in attack attempts on Mac users that will continue through the upcoming year. However, while malware is higher overall for OS X, there is also speculation that malware releases may come in opportunistic bubbles rather than follow a steady increase in marketshare of Apple's Mac platform, though it may be too soon to make such conclusions based on the data that is available.
Regardless, it is good to be prepared for threats should they arise. Even though OS X is relatively devoid of malware (and has no viral malware), treat any new files you download with caution, and do not install or run anything on your system unless you know and trust exactly where it came from.
To help Mac users out with this effort, Apple is gearing up for in increases in malware by adding new anti-malware features to OS X. Its XProtect technology, released in OS X 10.6 Snow Leopard, has gained automatic updating in the past year, and more recently Apple has announced Gatekeeper in the upcoming OS X Mountain Lion release, which will allow users to block all programs except for those from trusted sources from running on their systems.