MacDefender has morphed into something that only hours after Apple updated OS X to “defeat” the threat is able to defeat Apple’s defenses. AppleInsider reports that the new package is called “Mdinstall.pkg” and it gets past the security update Apple just released.
We were hit today with the warning while doing some searching for images in Google Image Search. The good news is that we were using Chrome, instead of Safari, and the browser prevented the download with a warning at the top of the screen telling us of the download and asking whether to allow it. Because we recognized the fake warning, we hit the back button and stopped the download to keep our system clean.
Apple needs to take one more step beyond its already aggressive steps and update Safari to have the option to open files after downloading turned off by default. For now, you should switch to an alternate browser like Chrome or follow these steps to turn off automatic file opening by Safari.
Another method of protecting your Mac and your wallet is to install Mac security software. Traditionally OS X users have been under the same pressures as Windows user when it comes to viruses and malware, but that looks to be changing. Check back in the coming days for a list of available Mac security software. There are a few good OS X security options out there including Avast for Mac which was just released by the popular developer of Windows antivirus software. If you prefer to get your software form the Mac App Store, check out the free VirusBarrier Express Mac security app. We haven’t had a chance to evaluate these apps, but they offer another tool in keeping your Mac free of malware and viruses.
The best solution is to keep malware off your Mac is to avoid opening files you download unless you were actively going to a site to download a specific file.