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iMac (27-inch Late 2009), iOS 5.1
Posted on Apr 7, 2012 3:24 AM
Q: If I haven't downloaded any of these malicious software, do I need to worry?
"Apple released a free software update (Security Update 2011-003) that will automatically find and remove Mac Defender malware and its known variants."
If you installed the latest security updates, you don't have to worry about MacDefender malware.