The company, Dr. Web, issued a report on Wednesday that claimed 550,000 computers running Mac OSX were subject to Flashback. Later, Sorokin Ivan, an analyst at Dr. Web, sent a tweet upgrading the figure to 600,000 and added that 274 were based in Cupertino, Calif., Apple's hometown. Fifty-seven percent of all Macs affected are in the U.S., while another 20% are based in Canada, according to the company.
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Flashback was originally discovered in September 2011 and was designed to disguise itself as an Adobe Flash Player installer, using Flash player logos. After installing Flashback, the malware seeks out user names and passwords that are stored on your Mac.
The resurgence of Flashback appears to take advantage of Java runtime for OSX. Apple issued a patch this week though it didn't mention Flashback by name. The patch is available for OSX 10.6 and 10.7 as well as for OSX Lion 2012-001.
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The attack comes after Apple continues to position OS X as a more secure alternative to Windows. "A Mac isn’t susceptible to the thousands of viruses plaguing Windows-based computers," reads a message on Apple's homepage. "That’s thanks to built-in defenses in Mac OS X that keep you safe, without any work on your part."
Image courtesy of Flickr, Adam Fagen.
This story originally published on Mashable here.