After acknowledging the presence of the Mac Defender scareware, Apple (NASDAQ: AAPL) wasted no time in issuing an update that directly addressed the malware. Security Update 2011-003, released on Tuesday, enabled Mac OS X to recognize the two existing variants of Mac Defender, and to stop Mac Defender in its tracks. Apple rounded out its aggressive stance by updating the OS to check in daily for new definitions. 

Well, the folks behind Mac Defender thumbed their noses at Apple--releasing a new variation of the malware to skirt Apple's new update. As reported on ZDNet, the new code first appeared in the wild just eight hours after Apple's security update--and acts exactly the same as its predecessors. Apple has since updated its signature database to include this new variant, but it remains to be seen if the black hats behind Mac Defender will release yet another version.

Regardless of the outcome of the Mac Defender saga, it's clear from this case that no system is immune to the threat of malware.

For more:
- check out this article at Infosecurity
- check out this article at Wired
- check out this article at ZDNet

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