Apple has just kicked out an update to Mac Security; an update has appeared in the Software Update with name of Mac Security Update 2011-003 available for immediate download and installation. This security update is promised by Apple which automatically founds and removed the Mac Defender Malware. The KB article HT4657 explains that, Apple has added a “OSX.MacDefender.A” definition to the malware check File Quarantine to remove the Mac Defender and its known variants from the Mac OS X 10.6.7.
According to the article published by Apple, explains that new security update will automatically searches for the Mac Defender malware and remove it, after removing it from the Mac it will notifies the user upon the completion of task.
You can also download the update from the download website